QUDT VOCAB Quantity Kinds Release 2.1.14
The "Absolute Activity" is the exponential of the ratio of the chemical potential to \(RT\) where \(R\) is the gas constant and \(T\) the thermodynamic temperature.
http://goldbook.iupac.org/A00019.html
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(\lambda_B = e^{\frac{\mu_B}{RT}}\), where \(\mu_B\) is the chemical potential of substance \(B\), \(R\) is the molar gas constant, and \(T\) is thermodynamic temperature.
\(\lambda_B\)
Absolute Activity
"Absolute Humidity" is an amount of water vapor, usually discussed per unit volume. Absolute humidity in air ranges from zero to roughly 30 grams per cubic meter when the air is saturated at \(30 ^\circ C\). The absolute humidity changes as air temperature or pressure changes. This is very inconvenient for chemical engineering calculations, e.g. for clothes dryers, where temperature can vary considerably. As a result, absolute humidity is generally defined in chemical engineering as mass of water vapor per unit mass of dry air, also known as the mass mixing ratio, which is much more rigorous for heat and mass balance calculations. Mass of water per unit volume as in the equation above would then be defined as volumetric humidity. Because of the potential confusion.
http://en.wikipedia.org/wiki/Humidity
http://en.wikipedia.org/wiki/Humidity#Absolute_humidity
http://www.iso.org/iso/catalogue_detail?csnumber=31890
\(AH = \frac{\mathcal{M}_\omega}{\vee_{net}}\),
where \(\mathcal{M}_\omega\) is the mass of water vapor per unit volume of total air and \(\vee_{net}\) is water vapor mixture.
AH
Absolute Humidity
"Absorbed Dose" (also known as Total Ionizing Dose, TID) is a measure of the energy deposited in a medium by ionizing radiation. It is equal to the energy deposited per unit mass of medium, and so has the unit \(J/kg\), which is given the special name Gray (\(Gy\)).
http://dbpedia.org/resource/Absorbed_dose
http://en.wikipedia.org/wiki/Absorbed_dose
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(D = \frac{d\bar{\varepsilon}}{dm}\), where \(d\bar{\varepsilon}\) is the mean energy imparted by ionizing radiation to an element of irradiated matter with the mass \(dm\).
D
Note that the absorbed dose is not a good indicator of the likely biological effect. 1 Gy of alpha radiation would be much more biologically damaging than 1 Gy of photon radiation for example. Appropriate weighting factors can be applied reflecting the different relative biological effects to find the equivalent dose. The risk of stoctic effects due to radiation exposure can be quantified using the effective dose, which is a weighted average of the equivalent dose to each organ depending upon its radiosensitivity. When ionising radiation is used to treat cancer, the doctor will usually prescribe the radiotherapy treatment in Gy. When risk from ionising radiation is being discussed, a related unit, the Sievert is used.
Absorbed Dose
\(L^2/T^3\)
\(m^2/s^3\)
http://www.answers.com/topic/absorbed-dose-rate
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(\dot{D} = \frac{dD}{dt}\), where \(dD\) is the increment of absorbed dose during time interval with duration \(dt\).
\(\dot{D}\)
"Absorbed Dose Rate" is the absorbed dose of ionizing radiation imparted at a given location per unit of time (second, minute, hour, or day).
Absorbed Dose Rate
https://en.wikipedia.org/wiki/Absorptance
https://www.researchgate.net/post/Absorptance_or_absorbance
\(\alpha = \frac{\Phi_a}{\Phi_m}\), where \(\Phi_a\) is the absorbed radiant flux or the absorbed luminous flux, and \(\Phi_m\) is the radiant flux or luminous flux of the incident radiation.
\(\alpha\)
Absorptance is the ratio of the radiation absorbed by a surface to that incident upon it. Also known as absorbance.
belongs to SOQ-ISO
Absorptance
Acceleration is the (instantaneous) rate of change of velocity. Acceleration may be either linear acceleration, or angular acceleration. It is a vector quantity with dimension \(length/time^{2}\) for linear acceleration, or in the case of angular acceleration, with dimension \(angle/time^{2}\). In SI units, linear acceleration is measured in \(meters/second^{2}\) (\(m \cdot s^{-2}\)) and angular acceleration is measured in \(radians/second^{2}\). In physics, any increase or decrease in speed is referred to as acceleration and similarly, motion in a circle at constant speed is also an acceleration, since the direction component of the velocity is changing.
http://dbpedia.org/resource/Acceleration
http://en.wikipedia.org/wiki/Acceleration
Acceleration
The acceleration of freely falling bodies under the influence of terrestrial gravity, equal to approximately 9.81 meters (32 feet) per second per second.
g
Acceleration Of Gravity
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Acceptor Density" is the number per volume of acceptor levels.
n_a
Acceptor Density
"Acceptor Ionization Energy" is the ionization energy of an acceptor.
http://en.wikipedia.org/wiki/Ionization_energy
http://www.iso.org/iso/catalogue_detail?csnumber=31897
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Acceptor Ionization Energy" is the ionization energy of an acceptor.
E_a
Acceptor Ionization Energy
http://en.wikipedia.org/wiki/Acoustic_impedance
\(Z_a= \frac{p}{q} = \frac{p}{vS}\), where \(p\) is the sound pressure, \(q\) is the sound volume velocity, \(v\) is sound particle velocity, and \(S\) is the surface area through which an acoustic wave of frequence \(f\) propagates.
Acoustic impedance at a surface is the complex quotient of the average sound pressure over that surface by the sound volume flow rate through that surface.
Z
Acoustic Impediance
http://en.wikipedia.org/wiki/Action_(physics)
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(S = \int Ldt\), where \(L\) is the Lagrange function and \(t\) is time.
An action is usually an integral over time. But for action pertaining to fields, it may be integrated over spatial variables as well. In some cases, the action is integrated along the path followed by the physical system. If the action is represented as an integral over time, taken a the path of the system between the initial time and the final time of the development of the system.
The evolution of a physical system between two states is determined by requiring the action be minimized or, more generally, be stationary for small perturbations about the true evolution. This requirement leads to differential equations that describe the true evolution. Conversely, an action principle is a method for reformulating differential equations of motion for a physical system as an equivalent integral equation. Although several variants have been defined (see below), the most commonly used action principle is Hamilton's principle.
S
Action
Action Time (sec)
Action Time
active-energy
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=601-01-19
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(W = \int_{t_1}^{t_2} p dt\), where \(p\) is instantaneous power and the integral interval is the time interval from \(t_1\) to \(t_2\).
http://www.iso.org/iso/catalogue_detail?csnumber=43012
"Active Energy" is the electrical energy transformable into some other form of energy.
W
Active Energy
\(Active Power\) is, under periodic conditions, the mean value, taken over one period \(T\), of the instantaneous power \(p\). In complex notation, \(P = \mathbf{Re} \; \underline{S}\), where \(\underline{S}\) is \(\textit{complex power}\)".
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=131-11-42
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(P = \frac{1}{T}\int_{0}^{T} pdt\), where \(T\) is the period and \(p\) is instantaneous power.
P
Active Power
"Activity" is the number of decays per unit time of a radioactive sample, the term used to characterise the number of nuclei which disintegrate in a radioactive substance per unit time. Activity is usually measured in Becquerels (\(Bq\)), where 1 \(Bq\) is 1 disintegration per second, in honor of the scientist Henri Becquerel.
http://dbpedia.org/resource/Radioactive_decay
http://en.wikipedia.org/wiki/Mass_number
http://en.wikipedia.org/wiki/Radioactive_decay
http://en.wikipedia.org/wiki/Radioactive_decay#Radioactive_decay_rates
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(A = Z + N\), where \(Z\) is the atomic number and \(N\) is the neutron number.
Variation \(dN\) of spontaneous number of nuclei \(N\) in a particular energy state, in a sample of radionuclide, due to spontaneous nuclear transitions from this state during an infinitesimal time interval, divided by its duration \(dt\), thus \(A = -\frac{dN}{dt}\).
A
Activity
http://en.wikipedia.org/wiki/Activity_coefficient
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(f_B = \frac{\lambda_B}{(\lambda_B^*x_B)}\), where \(\lambda_B\) the absolute activity of substance \(B\), \(\lambda_B^*\) is the absolute activity of the pure substance \(B\) at the same temperature and pressure, and \(x_B\) is the amount-of-substance fraction of substance \(B\).
An "Activity Coefficient" is a factor used in thermodynamics to account for deviations from ideal behaviour in a mixture of chemical substances. In an ideal mixture, the interactions between each pair of chemical species are the same (or more formally, the enthalpy change of solution is zero) and, as a result, properties of the mixtures can be expressed directly in terms of simple concentrations or partial pressures of the substances present e.g. Raoult's law. Deviations from ideality are accommodated by modifying the concentration by an activity coefficient.
f_B
Activity Coefficient
http://www.euronuclear.org/info/encyclopedia/activityconcentration.htm
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(c_A = \frac{A}{V}\), where \(A\) is the activity of a sample and \(V\) is its volume.
The "Activity Concentration", also known as volume activity, and activity density, is .
c_A
Activity Concentration
http://www.iso.org/iso/catalogue_detail?csnumber=43012
\(\overline{T_t}\)
"Activity Thresholds" are thresholds of sensitivity for radioactivity.
Activity Thresholds
http://www.iso.org/iso/catalogue_detail?csnumber=43012
"Adaptation" is the recovery of visual ability following exposure to light (dark adaptation).
Adaptation
"Admittance" is a measure of how easily a circuit or device will allow a current to flow. It is defined as the inverse of the impedance (\(Z\)).
http://en.wikipedia.org/wiki/Admittance
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=131-12-51
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(Y = \frac{1}{Z}\), where \(Z\) is impedance.
\(Y\)
Admittance
The "Alpha Disintegration Energy" is the sum of the kinetic energy of the \(\alpha\)-particle produced in the disintegration process and the recoil energy of the product atom in the reference frame in which the emitting nucleus is at rest before its disintegration.
\(Q_a\)
http://www.iso.org/iso/catalogue_detail?csnumber=31895
The "Alpha Disintegration Energy" is the sum of the kinetic energy of the alpha-particle produced in the disintegration process and the recoil energy of the product atom in the reference frame in which the emitting nucleus is at rest before its disintegration.
Alpha Disintegration Energy
http://dbpedia.org/resource/Altitude
Altitude or height is defined based on the context in which it is used (aviation, geometry, geographical survey, sport, and more). As a general definition, altitude is a distance measurement, usually in the vertical or "up" direction, between a reference datum and a point or object. The reference datum also often varies according to the context. [Wikipedia]
Altitude
The ambient pressure on an object is the pressure of the surrounding medium, such as a gas or liquid, which comes into contact with the object.
The SI unit of pressure is the pascal (Pa), which is a very small unit relative to atmospheric pressure on Earth, so kilopascals (\(kPa\)) are more commonly used in this context.
p_a
Ambient Pressure
"Amount of Substance" is a standards-defined quantity that measures the size of an ensemble of elementary entities, such as atoms, molecules, electrons, and other particles. It is sometimes referred to as chemical amount. The International System of Units (SI) defines the amount of substance to be proportional to the number of elementary entities present. The SI unit for amount of substance is \(mole\). It has the unit symbol \(mol\). The mole is defined as the amount of substance that contains an equal number of elementary entities as there are atoms in 0.012kg of the isotope carbon-12. This number is called Avogadro's number and has the value \(6.02214179(30) \times 10^{23}\). The only other unit of amount of substance in current use is the \(pound-mole\) with the symbol \(lb-mol\), which is sometimes used in chemical engineering in the United States. One \(pound-mole\) is exactly \(453.59237 mol\).
\(M\)
\(mol\)
http://dbpedia.org/resource/Amount_of_substance
http://en.wikipedia.org/wiki/Amount_of_substance
http://www.iso.org/iso/catalogue_detail?csnumber=31894
n
Amount of Substance
http://en.wikipedia.org/wiki/Amount_of_substance_concentration
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(C_B = \frac{n_B}{V}\), where \(n_B\) is the amount of substance \(B\) and \(V\) is the volume.
"Amount of Substance of Concentration of B" is defined as the amount of a constituent divided by the volume of the mixture.
C_B
Amount of Substance of Concentration of B
http://en.wikipedia.org/wiki/Amount_fraction
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(x_B = \frac{n_B}{n}\), where \(n_B\) is the amount of substance \(B\) and \(n\) is the total amount of substance.
"Amount of Substance of Fraction of B" is defined as tthe amount of a constituent divided by the total amount of all constituents in a mixture.
X_B
Amount of Substance of Fraction of B
\(N/M\)
fix the numerator and denominator dimensions
Amount of Substance per Unit Mass
The "Variation of Molar Mass" of a gas as a function of pressure.
Molar Mass variation due to Pressure
\(M/L^3\)
\(mol/m^3\)
http://www.ask.com/answers/72367781/what-is-defined-as-the-amount-of-substance-per-unit-of-volume
https://en.wikipedia.org/wiki/Molar_concentration
The amount of substance per unit volume is called the molar density. Molar density is an intensive property of a substance and depends on the temperature and pressure.
Amount of Substance per Unit Volume
The abstract notion of angle. Narrow concepts include plane angle and solid angle. While both plane angle and solid angle are dimensionless, they are actually length/length and area/area respectively.
http://dbpedia.org/resource/Angle
Angle
\(\alpha\)
Angle of attack is the angle between the oncoming air or relative wind and a reference line on the airplane or wing.
Angle Of Attack
http://en.wikipedia.org/wiki/Optical_rotation
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(\alpha\)
The "Angle of Optical Rotation" is the angle through which plane-polarized light is rotated clockwise, as seen when facing the light source, in passing through an optically active medium.
Angle of Optical Rotation
Angular acceleration is the rate of change of angular velocity over time. Measurement of the change made in the rate of change of an angle that a spinning object undergoes per unit time. It is a vector quantity. Also called Rotational acceleration. In SI units, it is measured in radians per second squared (\(rad/s^2\)), and is usually denoted by the Greek letter alpha.
U/T^2
\(/s^2\)
\(U/T^2\)
http://dbpedia.org/resource/Angular_acceleration
Angular Acceleration
"Angular Cross-section" is the cross-section for ejecting or scattering a particle into an elementary cone, divided by the solid angle \(d\Omega\) of that cone.
http://en.wikipedia.org/wiki/Cross_section_(physics)
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(\sigma = \int \sigma_\Omega d\Omega\)
\(\sigma_\Omega\)
Angular Cross-section
\(\theta\)
Angular distance travelled by orbiting vehicle measured from the azimuth of closest approach.
Angular Distance
"Angular frequency", symbol \(\omega\) (also referred to by the terms angular speed, radial frequency, circular frequency, orbital frequency, radian frequency, and pulsatance) is a scalar measure of rotation rate. Angular frequency (or angular speed) is the magnitude of the vector quantity angular velocity.
http://dbpedia.org/resource/Angular_frequency
http://en.wikipedia.org/wiki/Angular_frequency
http://www.iso.org/iso/catalogue_detail?csnumber=43012
\(\omega = 2\pi f\), where \(f\) is frequency.
\(\omega\)
belongs to SOQ-ISO
Angular Frequency
The Angular Impulse, also known as angular momentum, is the moment of linear momentum around a point. It is defined as\(H = \int Mdt\), where \(M\) is the moment of force and \(t\) is time.
http://dbpedia.org/resource/AngularMomentum
http://emweb.unl.edu/NEGAHBAN/EM373/note13/note.htm
http://www.iso.org/iso/catalogue_detail?csnumber=31889
H
Angular Impulse
\(L^2 \cdot M/T\)
\(kg \cdot m^2/s\)
http://dbpedia.org/resource/Angular_momentum
http://en.wikipedia.org/wiki/Angular_momentum
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(L = I\omega\), where \(I\) is the moment of inertia, and \(\omega\) is the angular velocity.
Angular Momentum of an object rotating about some reference point is the measure of the extent to which the object will continue to rotate about that point unless acted upon by an external torque. In particular, if a point mass rotates about an axis, then the angular momentum with respect to a point on the axis is related to the mass of the object, the velocity and the distance of the mass to the axis. While the motion associated with linear momentum has no absolute frame of reference, the rotation associated with angular momentum is sometimes spoken of as being measured relative to the fixed stars. \textit{Angular Momentum}, \textit{Moment of Momentum}, or \textit{Rotational Momentum", is a vector quantity that represents the product of a body's rotational inertia and rotational velocity about a particular axis.
L
Angular Momentum
"Angular Reciprocal Lattice Vector" is a vector whose scalar products with all fundamental lattice vectors are integral multiples of \(2\pi\).
http://www.matter.org.uk/diffraction/geometry/lattice_vectors.htm
http://www.iso.org/iso/catalogue_detail?csnumber=31897
G
Angular Reciprocal Lattice Vector
Angular Velocity refers to how fast an object rotates or revolves relative to another point.
\(/s\)
\(U/T\)
http://dbpedia.org/resource/Angular_velocity
https://en.wikipedia.org/wiki/Angular_velocity
The change of angle per unit time; specifically, in celestial mechanics, the change in angle of the radius vector per unit time.
Angular Velocity
http://en.wikipedia.org/wiki/Wavenumber
http://www.iso.org/iso/catalogue_detail?csnumber=31897
\(k = \frac{2\pi}{\lambda}= \frac{2\pi\upsilon}{\upsilon_p}=\frac{\omega}{\upsilon_p}\), where \(\upsilon\) is the frequency of the wave, \(\lambda\) is the wavelength, \(\omega = 2\pi \upsilon\) is the angular frequency of the wave, and \(\upsilon_p\) is the phase velocity of the wave.
Alternatively:
\(k = \frac{p}{\hbar}\), where \(p\) is the linear momentum of quasi free electrons in an electron gas and \(\hbar\) is the reduced Planck constant (\(h\) divided by \(2\pi\)); for phonons, its magnitude is \(k = \frac{2\pi}{\lambda}\), where \(\lambda\) is the wavelength of the lattice vibrations.
"wavenumber" is the spatial frequency of a wave - the number of waves that exist over a specified distance. More formally, it is the reciprocal of the wavelength. It is also the magnitude of the wave vector.
k
belongs to SOQ-ISO
Angular Wavenumber
Apogee radius of an elliptical orbit
r_2
Apogee Radius
"Apparent Power" is the product of the rms voltage \(U\) between the terminals of a two-terminal element or two-terminal circuit and the rms electric current I in the element or circuit. Under sinusoidal conditions, the apparent power is the modulus of the complex power.
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=131-11-41
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(\left | \underline{S} \right | = UI\), where \(U\) is rms value of voltage and \(I\) is rms value of electric current.
\(\left | \underline{S} \right |\)
Apparent Power
cm^2
\(m^2\)
\(L^2\)
http://dbpedia.org/resource/Area
Area is a quantity expressing the two-dimensional size of a defined part of a surface, typically a region bounded by a closed curve.
Area
\(L^2 \cdot U\)
\(m^2\)
Area Angle
\(ft^2/s\)
\(m^2/s\)
\(L^2/T\)
Area per Time
Area Ratio
\(K \cdot m^2\)
\(\Theta \cdot L^2\)
Area Temperature
\(L^2/\Theta\)
\(m^2/K\)
http://en.wikipedia.org/area_thermal_expansion
When the temperature of a substance changes, the energy that is stored in the intermolecular bonds between atoms changes. When the stored energy increases, so does the length of the molecular bonds. As a result, solids typically expand in response to heating and contract on cooling; this dimensional response to temperature change is expressed by its coefficient of thermal expansion.
Area Thermal Expansion
\(L^2 \cdot T\)
\(m^2 \cdot s\)
Area Time
Area Time Temperature
heat-flow-rate
http://en.wikipedia.org/wiki/Rate_of_heat_flow
\(\varphi = \frac{\Phi}{A}\), where \(\Phi\) is heat flow rate and \(A\) is area.
http://www.iso.org/iso/catalogue_detail?csnumber=31890
Density of heat flow rate.
φ
Aeric Heat Flow Rate
An Asset is an economic resource owned by a business or company. Simply stated, assets are things of value that can be readily converted into cash (although cash itself is also considered an asset).
Asset
The pressure exerted by the weight of the air above it at any point on the earth's surface. At sea level the atmosphere will support a column of mercury about \(760 mm\) high. This decreases with increasing altitude. The standard value for the atmospheric pressure at sea level in SI units is \(101,325 pascals\).
http://dbpedia.org/resource/Atmospheric_pressure
http://www.oxfordreference.com/views/ENTRY.html?subview=Main&entry=t83.e178
Atmospheric Pressure
http://reference.iucr.org/dictionary/Atomic_scattering_factor
http://www.iso.org/iso/catalogue_detail?csnumber=31897
\(f = \frac{E_a}{E_e}\), where \(E_a\) is the radiation amplitude scattered by the atom and \(E_e\) is the radiation ampliture scattered by a single electron.
"Atom Scattering Factor" is measure of the scattering power of an isolated atom.
f
Atom Scattering Factor
http://en.wikipedia.org/wiki/Attenuation_coefficient
\(\mu_a = -\frac{\mu}{n}\), where \(\mu\) is the linear attenuation coefficient and \(n\) is the number density of the atoms in the substance.
http://www.iso.org/iso/catalogue_detail?csnumber=31895
"Atomic Attenuation Coefficient" is a measurement of how strongly a chemical species or substance absorbs or scatters light at a given wavelength, per the number of atoms in the substance.
μₐ
Atomic Attenuation Coefficient
http://www.answers.com/topic/atomic-charge
The electric charge of an ion, equal to the number of electrons the atom has gained or lost in its ionization multiplied by the charge on one electron.
Atomic Charge
http://en.wikipedia.org/wiki/Atomic_mass
http://www.iso.org/iso/catalogue_detail?csnumber=31895
The "Atomic Mass" is the mass of a specific isotope, most often expressed in unified atomic mass units.
m_a
Atomic Mass
http://en.wikipedia.org/wiki/Atomic_number
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31895
http://www.iso.org/iso/catalogue_detail?csnumber=31894
The "Atomic Number", also known as the proton number, is the number of protons found in the nucleus of an atom and therefore identical to the charge number of the nucleus. A nuclide is a species of atom with specified numbers of protons and neutrons. Nuclides with the same value of Z but different values of N are called isotopes of an element. The ordinal number of an element in the periodic table is equal to the atomic number. The atomic number equals the charge of the nucleus in units of the elementary charge.
Z
Atomic Number
http://en.wikipedia.org/wiki/Attenuation_coefficient
\(F(x) = Ae^{-\alpha x} \cos{[\beta (x - x_0)]}\), then \(\alpha\) is the attenuation coefficient and \(\beta\) is the phase coefficient.
\(\alpha\)
The attenuation coefficient is a quantity that characterizes how easily a material or medium can be penetrated by a beam of light, sound, particles, or other energy or matter. A large attenuation coefficient means that the beam is quickly "attenuated" (weakened) as it passes through the medium, and a small attenuation coefficient means that the medium is relatively transparent to the beam. The Attenuation Coefficient is also called linear attenuation coefficient, narrow beam attenuation coefficient, or absorption coefficient.
belongs to SOQ-ISO
Attenuation Coefficient
http://www.iso.org/iso/catalogue_detail?csnumber=43012
\(\overline{T_a}\)
"Auditory Thresholds" is the thresholds of sensitivity to auditory signals and other input to the ear or the sense of hearing.
Auditory Thresholds
H
Magnetic Fields surround magnetic materials and electric currents and are detected by the force they exert on other magnetic materials and moving electric charges. The electric and magnetic fields are two interrelated aspects of a single object, called the electromagnetic field. A pure electric field in one reference frame is observed as a combination of both an electric field and a magnetic field in a moving reference frame. The Auxillary Magnetic Field, H characterizes how the true Magnetic Field B influences the organization of magnetic dipoles in a given medium.
Auxillary Magnetic Field
\(W_i = \frac{E_k}{N_i}\), where \(E_k\) is the initial kinetic energy of an ionizing charged particle and \(N_i\) is the total ionization produced by that particle.
http://www.iso.org/iso/catalogue_detail?csnumber=31895
"Average Energy Loss per Elementary Charge Produced" is also referred to as average energy loss per ion pair formed.
W_i
Average Energy Loss per Elementary Charge Produced
AHEP
Average Head End Pressure
http://everything2.com/title/Average+logarithmic+energy+decrement+per+collision
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(\xi\)
"Average Logarithmic Energy Decrement" is a measure of the amount of energy a neutron loses upon colliding with various nuclei. It is the average value of the increase in lethargy in elastic collisions between neutrons and nuclei whose kinetic energy is negligible compared with that of the neutrons.
Average Logarithmic Energy Decrement
Avg Specific Impulse (lbf-sec/lbm)
Average Specific Impulse
Average Vacuum Thrust
AVT
http://dbpedia.org/resource/Torque
http://en.wikipedia.org/wiki/Bending_moment
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(M_b = M \cdot e_Q\), where \(M\) is the momentof force and \(e_Q\) is a unit vector directed along a \(Q-axis\) with respect to which the torque is considered.
A bending moment exists in a structural element when a moment is applied to the element so that the element bends. It is the component of moment of force perpendicular to the longitudinal axis of a beam or a shaft.
M_b
Bending Moment of Force
http://en.wikipedia.org/wiki/Decay_energy
http://www.iso.org/iso/catalogue_detail?csnumber=31895
"Beta Disintegration Energy" is the energy released by a beta particle radioactive decay. It is the sum of the maximum beta-particle kinetic energy and the recoil energy of the atom produced in the reference frame in which the emitting nucleus is at rest before its disintegration.
Qᵦ
Beta Disintegration Energy
\(\theta\)
Pitch angle in bevel gears is the angle between an element of a pitch cone and its axis. In external and internal bevel gears, the pitch angles are respectively less than and greater than 90 degrees.
Bevel Gear Pitch Angle
http://encyclopedia2.thefreedictionary.com/binding+fraction
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(b = \frac{B_r}{A}\), where \(B_r\) is the relative mass defect and \(A\) is the nucleon number.
The "Binding Fraction" is the ratio of the binding energy of a nucleus to the atomic mass number.
b
Binding Fraction
The blood sugar level, blood sugar concentration, or blood glucose level is the amount of glucose present in the blood of humans and other animals. Glucose is a simple sugar and approximately 4 grams of glucose are present in the blood of humans at all times. The body tightly regulates blood glucose levels as a part of metabolic homeostasis. Glucose is stored in skeletal muscle and liver cells in the form of glycogen;[2] in fasted individuals, blood glucose is maintained at a constant level at the expense of glycogen stores in the liver and skeletal muscle. [Wikipedia] \(\\\) There are two main methods of describing concentrations: by weight, and by molecular count. Weights are in grams, molecular counts in moles. A mole is \(6.022\times 10^{23}\) molecules.) In both cases, the unit is usually modified by \(milli-\) or \(micro-\) or other prefix, and is always \(per\) some volume, often a liter. Conversion factors depend on the molecular weight of the substance in question. \(\\\) \(mmol/L\) is millimoles/liter, and is the world standard unit for measuring glucose in blood. Specifically, it is the designated SI (Systeme International) unit. 'World standard' is not universal; not only the US but a number of other countries use mg/dl. A mole is about \(6\times 10^{23}\) molecules. \(\\\) \(mg/dL\) (milligrams/deciliter) is the traditional unit for measuring bG (blood glucose). There is a trend toward using \(mmol/L\) however mg/dL is much in practice. Some use is made of \(mmol/L\) as the primary unit with \(mg/dL\) quoted in parentheses. This acknowledges the large base of health care providers, researchers and patients who are already familiar with \(mg/dL|).
http://www.faqs.org/faqs/diabetes/faq/part1/section-9.html
citation: https://en.wikipedia.org/wiki/Blood_sugar_level
Blood Glucose Level
The blood sugar level, blood sugar concentration, or blood glucose level is the amount of glucose present in the blood of humans and other animals. Glucose is a simple sugar and approximately 4 grams of glucose are present in the blood of humans at all times. The body tightly regulates blood glucose levels as a part of metabolic homeostasis. Glucose is stored in skeletal muscle and liver cells in the form of glycogen;[2] in fasted individuals, blood glucose is maintained at a constant level at the expense of glycogen stores in the liver and skeletal muscle. [Wikipedia] \(\\\) There are two main methods of describing concentrations: by weight, and by molecular count. Weights are in grams, molecular counts in moles. A mole is \(6.022\times 10^{23}\) molecules.) In both cases, the unit is usually modified by \(milli-\) or \(micro-\) or other prefix, and is always \(per\) some volume, often a liter. Conversion factors depend on the molecular weight of the substance in question. \(\\\) \(mmol/L\) is millimoles/liter, and is the world standard unit for measuring glucose in blood. Specifically, it is the designated SI (Systeme International) unit. 'World standard' is not universal; not only the US but a number of other countries use mg/dl. A mole is about \(6\times 10^{23}\) molecules. \(\\\) \(mg/dL\) (milligrams/deciliter) is the traditional unit for measuring bG (blood glucose). There is a trend toward using \(mmol/L\) however mg/dL is much in practice. Some use is made of \(mmol/L\) as the primary unit with \(mg/dL\) quoted in parentheses. This acknowledges the large base of health care providers, researchers and patients who are already familiar with \(mg/dL|).
http://www.faqs.org/faqs/diabetes/faq/part1/section-9.html
citation: https://en.wikipedia.org/wiki/Blood_sugar_level
Blood Glucose Level by Mass
\(\textit{Body Mass Index}\), BMI, is an index of weight for height, calculated as: \(BMI = \frac{M_{body}}{H}\), where \(M_{body}\) is body mass in kg, and \(H\) is height in metre. The BMI has been used as a guideline for defining whether a person is overweight because it minimizes the effect of height, but it does not take into consideration other important factors, such as age and body build. The BMI has also been used as an indicator of obesity on the assumption that the higher the index, the greater the level of body fat.
http://www.oxfordreference.com/view/10.1093/acref/9780198631477.001.0001/acref-9780198631477-e-254
BMI
Body Mass Index
BMI
http://reference.iucr.org/dictionary/Bragg_angle
http://www.iso.org/iso/catalogue_detail?csnumber=31897
\(2d\sin{\vartheta} = n\lambda \)
\(\vartheta\)
"Bragg Angle" describes the condition for a plane wave to be diffracted from a family of lattice planes, the angle between the wavevector of the incident plane wave, and the lattice planes.
Bragg Angle
http://dbpedia.org/resource/Length
http://en.wiktionary.org/wiki/breadth
http://www.iso.org/iso/catalogue_detail?csnumber=43012
"Breadth" is the extent or measure of how broad or wide something is.
b
Breadth
B
Buckling Factor
http://en.wikipedia.org/wiki/Bulk_modulus
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(K = \frac{p}{\vartheta}\), where \(p\) is pressure and \(\vartheta\) is volume strain.
The bulk modulus of a substance measures the substance's resistance to uniform compression. It is defined as the ratio of the infinitesimal pressure increase to the resulting relative decrease of the volume.
K
Bulk Modulus
http://en.wikipedia.org/wiki/Burgers_vector
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Burgers Vector" is the vector characterizing a dislocation, i.e. the closing vector in a Burgers circuit encircling a dislocation line.
b
Burgers Vector
Burn Rate
t
Burn Time
cg
http://www.grc.nasa.gov/WWW/k-12/airplane/cg.html
Center of Gravity in the X axis
cg
http://www.grc.nasa.gov/WWW/k-12/airplane/cg.html
Center of Gravity in the Y axis
cg
http://www.grc.nasa.gov/WWW/k-12/airplane/cg.html
Center of Gravity in the X axis
The point at which the distributed mass of a composite body can be acted upon by a force without inducing any rotation of the composite body.
R
http://en.wikipedia.org/wiki/Center_of_mass
Center of Mass (CoM)
COM
Contractual mass requirement of a delivered item. Note that The term 'control mass' is sometimes utilized as a limit in lieu of CEI mass when a CEI mass does not exist. The term 'Interface Control Document Mass' is another alternative for specifying a contractual mass requirement.
Contract End Item (CEI) Specification Mass.
CEI
The upper design gross mass limit of a system at a specified mission event against which margins are calculated after accounting for basic masses of flight hardware, MGA, and uncertainties. It may include propellants, crew, and cargo.
Control Mass.
http://en.wikipedia.org/wiki/Partition_function_(statistical_mechanics)
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(Z = \sum_r e^{-\frac{E_r}{kT}}\), where the sum is over all quantum states consistent with given energy, volume, external fields, and content, \(E_r\) is the energy in the \(rth\) quantum state, \(k\) is the Boltzmann constant, and \(T\) is thermodynamic temperature.
A "Canonical Partition Function" applies to a canonical ensemble, in which the system is allowed to exchange heat with the environment at fixed temperature, volume, and number of particles.
Z
Canonical Partition Function
\(A^2 \cdot s^4/kg \cdot m^2\)
\(I^2 \cdot T^4/L^2 \cdot M\)
http://dbpedia.org/resource/Capacitance
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
http://www.iso.org/iso/catalogue_detail?csnumber=43012
\(C = Q/U\), where \(Q\) is electric charge and \(V\) is voltage.
"Capacitance" is the ability of a body to hold an electrical charge; it is quantified as the amount of electric charge stored for a given electric potential. Capacitance is a scalar-valued quantity.
C
Capacitance
http://dbpedia.org/resource/Capacity
In computer operations, (a) the largest quantity which can be stored, processed, or transferred; (b) the largest number of digits or characters which may regularly be processed; (c) the upper and lower limits of the quantities which may be processed. In other contexts, the amount of material that can be stored, such as fuel or food.
TBD
Capacity
http://en.wikipedia.org/wiki/Carrier_lifetime
http://www.iso.org/iso/catalogue_detail?csnumber=31897
\(\tau, \tau_n, \tau_p\)
"Carrier LifetIme" is a time constant for recombination or trapping of minority charge carriers in semiconductors.
Carrier LifetIme
area
http://en.wikipedia.org/wiki/Area
\(A = \int\int dxdy\), where \(x\) and \(y\) are cartesian coordinates.
http://www.iso.org/iso/catalogue_detail?csnumber=43012
"Area" is a quantity that expresses the extent of a two-dimensional surface or shape, or planar lamina, in the plane.
A
Cartesian Area
http://en.wikipedia.org/wiki/Cartesian_coordinate_system
http://www.iso.org/iso/catalogue_detail?csnumber=43012
"Cartesian Coordinates" specify each point uniquely in a plane by a pair of numerical coordinates, which are the signed distances from the point to two fixed perpendicular directed lines, measured in the same unit of length.
x, y, z
Cartesian Coordinates
http://en.wikipedia.org/wiki/Volume
http://www.iso.org/iso/catalogue_detail?csnumber=43012
\(V = \int\int\int dxdydz\), where \(x\), \(y\), and \(z\) are cartesian coordinates.
"Volume" is the quantity of three-dimensional space enclosed by some closed boundary, for example, the space that a substance (solid, liquid, gas, or plasma) or shape occupies or contains.
V
Volume
An index of the actual or potential activity of a catalyst. The catalytic activity of an enzyme or an enzyme-containing preparation is defined as the property measured by the increase in the rate of conversion of a specified chemical reaction that the enzyme produces in a specified assay system. Catalytic activity is an extensive quantity and is a property of the enzyme, not of the reaction mixture; it is thus conceptually different from rate of conversion although measured by and equidimensional with it. The unit for catalytic activity is the \(katal\); it may also be expressed in mol \(s^{-1}\). Dimensions: \(N T^{-1}\). Former terms such as catalytic ability, catalytic amount, and enzymic activity are no er recommended. Derived quantities are molar catalytic activity, specific catalytic activity, and catalytic activity concentration. Source(s): <a href="http://www.answers.com/topic/catalytic-activity-biochemistry">www.answers.com</a>
\(M/T\)
\(mol/s\)
http://dbpedia.org/resource/Catalysis
Catalytic Activity
http://www.iso.org/iso/catalogue_detail?csnumber=31890
"Celsius Temperature", the thermodynamic temperature \(T_0\), is exactly \(0.01\)kelvin below the thermodynamic temperature of the triple point of water.
\(t = T - T_0\), where \(T\) is Thermodynamic Temperature and \(T_0 = 273.15 K\).
"Celsius Temperature", the thermodynamic temperature T_0, is exactly 0.01 kelvin below the thermodynamic temperature of the triple point of water.
Celsius temperature
Characteristic impedance at a point in a non-dissipative medium and for a plane progressive wave, the quotient of the sound pressure \(p\) by the component of the sound particle velocity \(v\) in the direction of the wave propagation.
http://en.wikipedia.org/wiki/Acoustic_impedance#Characteristic_acoustic_impedance
\(Z_c = pc\), where \(p\) is the sound pressure and \(c\) is the phase speed of sound.
Z
belongs to SOQ-ISO
Characteristic Acoustic Impedance
Characteristic velocity or \(c^{*}\) is a measure of the combustion performance of a rocket engine independent of nozzle performance, and is used to compare different propellants and propulsion systems.
\(c^{*}\)
Characteristic Velocity
http://en.wikipedia.org/wiki/Charge_number
http://www.iso.org/iso/catalogue_detail?csnumber=31894
The "Charge Number", or just valance of an ion is the coefficient that, when multiplied by the elementary charge, gives the ion's charge.
z
Charge Number
http://en.wikipedia.org/wiki/Chemical_affinity
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(A = -\sum \nu_b\mu_B\), where \(\nu_b\) is the stoichiometric number of substance \(B\) and \(\mu_B\) is the chemical potential of substance \(B\).
In chemical physics and physical chemistry, "Chemical Affinity" is the electronic property by which dissimilar chemical species are capable of forming chemical compounds. Chemical affinity can also refer to the tendency of an atom or compound to combine by chemical reaction with atoms or compounds of unlike composition.
A
Chemical Affinity
http://en.wikipedia.org/wiki/Chemical_potential
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(\mu_B = (\frac{\partial G}{\partial n_B})_{T,p,n_i}\), where \(G\) is Gibbs energy, and \(n_B\) is the amount of substance \(B\).
\(\mu_B\)
"Chemical Potential", also known as partial molar free energy, is a form of potential energy that can be absorbed or released during a chemical reaction.
Chemical Potential
http://dbpedia.org/resource/Circulation_%28fluid_dynamics%29
\(\Gamma\)
In fluid dynamics, circulation is the line integral around a closed curve of the fluid velocity. It has dimensions of length squared over time.
Circulation
r_o
Closest Approach Radius
\(M/\Theta \cdot T^3\)
\(kg/K \cdot s^3\)
\(heat-xfer-coeff\)
http://en.wikipedia.org/wiki/Heat_transfer_coefficient
"Coefficient of Heat Transfer", in thermodynamics and in mechanical and chemical engineering, is used in calculating the heat transfer, typically by convection or phase transition between a fluid and a solid. The heat transfer coefficient is the proportionality coefficient between the heat flux, that is heat flow per unit area, \(q/A\), and the thermodynamic driving force for the flow of heat (that is, the temperature difference, \( \bigtriangleup T \)). Areic heat flow rate divided by thermodynamic temperature difference. In building technology, the \(\textit{Coefficient of Heat Transfer}\), is often called \(\textit{thermal transmittance}\), with the symbol \(U\). \(\textit{Coefficient of Heat Transfer}\), has SI units in watts per squared meter kelvin: \(W/(m^2 \cdot K)\) .
\(K = \frac{\varphi}{T}\), where \(\varphi\) is areic heat flow rate and \(T\) is thermodynamic temperature difference.
\(\kappa\)
"Coefficient of Heat Transfer", in thermodynamics and in mechanical and chemical engineering, is used in calculating the heat transfer, typically by convection or phase transition between a fluid and a solid. The heat transfer coefficient is the proportionality coefficient between the heat flux, that is heat flow per unit area, q/A, and the thermodynamic driving force for the flow of heat (that is, the temperature difference, (Delta T). Areic heat flow rate divided by thermodynamic temperature difference. In building technology, the "Coefficient of Heat Transfer", is often called "thermal transmittance}" with the symbol "U". It has SI units in watts per squared meter kelvin.
Coefficient of heat transfer
\(\textit{Coercivity}\), also referred to as \(\textit{Coercive Field Strength}\), is the magnetic field strength to be applied to bring the magnetic flux density in a substance from its remaining magnetic flux density to zero. This is defined as the coercive field strength in a substance when either the magnetic flux density or the magnetic polarization and magnetization is brought from its value at magnetic saturation to zero by monotonic reduction of the applied magnetic field strength. The quantity which is brought to zero should be stated, and the appropriate symbol used: \(H_{cB}\), \(H_{cJ}\) or \(H_{cM}\) for the coercivity relating to the magnetic flux density, the magnetic polarization or the magnetization respectively, where \(H_{cJ} = H_{cM}\).
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=121-12-69
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
H_{c,B}
Coercivity
http://en.wikipedia.org/wiki/Coherence_length
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Coherence Length" characterizes the distance in a superconductor over which the effect of a perturbation is appreciable.
ξ
Coherence Length
http://www.iso.org/iso/catalogue_detail?csnumber=43012
\(\overline{T_c}\)
"Cold Receptor Threshold" is the threshold of cold-sensitive free nerve-ending.
Cold Receptor Threshold
http://www.iso.org/iso/catalogue_detail?csnumber=43012
\(h = h_r + h_c + h_k\), where \(h_r\) is the linear radiative heat transfer coefficient, \(h_c\) is the convective heat transfer coefficient, and \(h_k\) is the conductive heat transfer coefficient.
"Combined Non Evaporative Heat Transfer Coefficient" is the
h
Combined Non Evaporative Heat Transfer Coefficient
T_c
Combustion Chamber Temperature
"Complex Power", under sinusoidal conditions, is the product of the phasor \(U\) representing the voltage between the terminals of a linear two-terminal element or two-terminal circuit and the complex conjugate of the phasor \(I\) representing the electric current in the element or circuit.
\(complex-power\)
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=131-11-39
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(\underline{S} = \underline{U}\underline{I^*}\), where \(\underline{U}\) is voltage phasor and \(\underline{I^*}\) is the complex conjugate of the current phasor.
\(\underline{S}\)
Complex Power
http://en.wikipedia.org/wiki/Compressibility
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(\chi = -(\frac{1}{V})\frac{dV}{d\rho}\), where \(V\) is volume and \(p\) is pressure.
\(\chi\)
Compressibility is a measure of the relative volume change of a fluid or solid as a response to a pressure (or mean stress) change.
Compressibility
The compressibility factor (\(Z\)) is a useful thermodynamic property for modifying the ideal gas law to account for the real gas behaviour. The closer a gas is to a phase change, the larger the deviations from ideal behavior. It is simply defined as the ratio of the molar volume of a gas to the molar volume of an ideal gas at the same temperature and pressure. Values for compressibility are calculated using equations of state (EOS), such as the virial equation and van der Waals equation. The compressibility factor for specific gases can be obtained, with out calculation, from compressibility charts. These charts are created by plotting Z as a function of pressure at constant temperature.
http://www.iso.org/iso/catalogue_detail?csnumber=31890
Z
Compressibility Factor
http://dbpedia.org/resource/Concentration
http://en.wikipedia.org/wiki/Concentration
In chemistry, concentration is defined as the abundance of a constituent divided by the total volume of a mixture. Furthermore, in chemistry, four types of mathematical description can be distinguished: mass concentration, molar concentration, number concentration, and volume concentration. The term concentration can be applied to any kind of chemical mixture, but most frequently it refers to solutes in solutions.
Concentration
\(\textit{Conductance}\), for a resistive two-terminal element or two-terminal circuit with terminals A and B, quotient of the electric current i in the element or circuit by the voltage \(u_{AB}\) between the terminals: \(G = \frac{1}{R}\), where the electric current is taken as positive if its direction is from A to B and negative in the opposite case. The conductance of an element or circuit is the inverse of its resistance.
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=131-12-06
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(G = Re\underline{Y}\), where \(\underline{Y}\) is admittance.
Alternatively:
\(G = \frac{1}{R}\), where \(R\) is resistance.
G
Conductance
http://www.iso.org/iso/catalogue_detail?csnumber=43012
"Conduction Speed" is the speed of impulses in nerve fibers.
c
Conduction Speed
http://www.iso.org/iso/catalogue_detail?csnumber=43012
\(\Phi_k\)
"Conductive Heat Transfer Rate" is proportional to temperature gradient and area of contact.
Conductive Heat Transfer Rate
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=121-12-03
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(\mathbf{J} = \sigma \mathbf{E}\), where \(\mathbf{J}\) is electric current density, and \(\mathbf{E}\) is electric field strength.
\(\gamma\)
\(\sigma\)
"Conductivity" is a scalar or tensor quantity the product of which by the electric field strength in a medium is equal to the electric current density. For an isotropic medium the conductivity is a scalar quantity; for an anisotropic medium it is a tensor quantity.
Conductivity
http://www.iso.org/iso/catalogue_detail?csnumber=43012
\(\Phi_c\)
"Convective Heat Transfer" is convective heat transfer coefficient multiplied by temperature difference and exchange area.
Convective Heat Transfer
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=161-03-18
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
For inductive coupling between two inductive elements, \(k = \frac{\left | L_{mn} \right |}{\sqrt{L_m L_n}}\), where \(L_m\) and \(L_n\) are their self inductances, and \(L_{mn}\) is their mutual inductance.
"Coupling Factor" is the ratio of an electromagnetic quantity, usually voltage or current, appearing at a specified location of a given circuit to the corresponding quantity at a specified location in the circuit from which energy is transferred by coupling.
k
Coupling Factor
http://en.wikipedia.org/wiki/Cross_section_(physics)
http://www.iso.org/iso/catalogue_detail?csnumber=31895
"Cross-section" is used to express the likelihood of interaction between particles. For a specified target particle and for a specified reaction or process produced by incident charged or uncharged particles of specified type and energy, it is the mean number of such reactions or processes divided by the incident-particle fluence.
σ
Cross-section
A
Cross-sectional Area
\(A^3 \cdot s^7/kg^2 \cdot m\)
\(I^3 \cdot T^7/L \cdot M^2\)
Cubic Electric Dipole Moment per Square Energy
\(cubic-exp-coef\)
http://www.iso.org/iso/catalogue_detail?csnumber=31890
\(\alpha_V = \frac{1}{V} \; \frac{dV}{dT}\), where \(V\) is \(volume\) and \(T\) is thermodynamic temperature.
\(\alpha_v\)
Cubic Expansion Coefficient
http://en.wikipedia.org/wiki/Curie_temperature
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Curie Temperature" is the critical thermodynamic temperature of a ferromagnet.
T_C
Curie Temperature
http://dbpedia.org/resource/Currency
http://en.wikipedia.org/wiki/Currency
In economics, currency is a generally accepted medium of exchange. These are usually the coins and banknotes of a particular government, which comprise the physical aspects of a nation's money supply. The other part of a nation's money supply consists of bank deposits (sometimes called deposit money), ownership of which can be transferred by means of cheques, debit cards, or other forms of money transfer. Deposit money and currency are money in the sense that both are acceptable as a means of payment.
Currency
\(current-linkage\)
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=121-11-60
\(\Theta\)
"Current Linkage" is the net electric current through a surface delimited by a closed loop.
Current Linkage
The canonical example of extrinsic curvature is that of a circle, which has curvature equal to the inverse of its radius everywhere. Smaller circles bend more sharply, and hence have higher curvature. The curvature of a smooth curve is defined as the curvature of its osculating circle at each point. The osculating circle of a sufficiently smooth plane curve at a given point on the curve is the circle whose center lies on the inner normal line and whose curvature is the same as that of the given curve at that point. This circle is tangent to the curve at the given point. The magnitude of curvature at points on physical curves can be measured in \(diopters\) (also spelled \(dioptre\)) — this is the convention in optics.
http://dbpedia.org/resource/Curvature
http://en.wikipedia.org/wiki/Curvature
The canonical example of extrinsic curvature is that of a circle, which has curvature equal to the inverse of its radius everywhere. Smaller circles bend more sharply, and hence have higher curvature. The curvature of a smooth curve is defined as the curvature of its osculating circle at each point. The osculating circle of a sufficiently smooth plane curve at a given point on the curve is the circle whose center lies on the inner normal line and whose curvature is the same as that of the given curve at that point. This circle is tangent to the curve at the given point.
That is, given a point P on a smooth curve C, the curvature of C at P is defined to be 1/R where R is the radius of the osculating circle of C at P. The magnitude of curvature at points on physical curves can be measured in diopters (also spelled dioptre) — this is the convention in optics. [Wikipedia],
Curvature
http://en.wikipedia.org/wiki/Curvature
http://www.iso.org/iso/catalogue_detail?csnumber=43012
\(\kappa = \frac{1}{\rho}\), where \(\rho\) is the radius of the curvature.
\(\kappa\)
In mathematics "Curvature" is the amount by which a geometric object deviates from being flat, or straight in the case of a line, but this is defined in different ways depending on the context.
Curvature
http://en.wikipedia.org/wiki/Electron_cyclotron_resonance
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(\omega_c = \frac{\left | q \right |}{m}B\), where \(q\) is the electric charge, \(m\) is its mass, and \(B\) is the magnetic flux density.
\(\omega_c\)
The "Cyclotron Angular Frequency" describes angular momentum vector precession about the external field axis with an angular frequency.
Larmor Angular Frequency
\(\bigtriangleup v\)
The change in translational velocity including all losses for a propulsive system or module. Delta-V losses include, but are not limited to, gravity losses and steering losses.
http://en.wikipedia.org/wiki/Delta-v
Delta-V
Mass of a system without the propellants, pressurants, reserve or residual fluids, personnel and personnel provisions, and cargo.
Dry Mass
http://dbpedia.org/resource/Data_rate
The frequency derived from the period of time required to transmit one bit. This represents the amount of data transferred per second by a communications channel or a computing or storage device. Data rate is measured in units of bits per second (written "b/s" or "bps"), bytes per second (Bps), or baud. When applied to data rate, the multiplier prefixes "kilo-", "mega-", "giga-", etc. (and their abbreviations, "k", "M", "G", etc.) always denote powers of 1000. For example, 64 kbps is 64,000 bits per second. This contrasts with units of storage which use different prefixes to denote multiplication by powers of 1024, for example 1 kibibit = 1024 bits.
Data Rate
http://en.wikipedia.org/wiki/Debye–Waller_factor
http://www.iso.org/iso/catalogue_detail?csnumber=31897
\(u = R - R_0\), where \(R\) is the particle position vector and \(R_0\) is the equilibrium position vector of a particle.
"Debye-Waller Factor" (DWF), named after Peter Debye and Ivar Waller, is used in condensed matter physics to describe the attenuation of x-ray scattering or coherent neutron scattering caused by thermal motion. Also, a factor by which the intensity of a diffraction line is reduced because of the lattice vibrations.
D, B
Debye-Waller Factor
http://lamp.tu-graz.ac.at/~hadley/ss1/phonons/table/dosdebye.html
http://www.iso.org/iso/catalogue_detail?csnumber=31897
\(\omega_b\)
"Debye Angular Frequency" is the cut-off angular frequency in the Debye model of the vibrational spectrum of a solid.
Debye Angular Frequency
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Debye Angular Wavenumber" is the cut-off angular wavenumber in the Debye model of the vibrational spectrum of a solid.
q_D
Debye Angular Wavenumber
http://en.wikipedia.org/wiki/Debye_model
http://www.iso.org/iso/catalogue_detail?csnumber=31897
\(\Theta_D = \frac{\hbar\omega_D}{k}\), where \(k\) is the Boltzmann constant, \(\hbar\) is the reduced Planck constant, and \(\omega_D\) is the Debye angular frequency.
\(\Theta_D\)
"Debye Temperature" is the temperature at which the highest-frequency mode (and hence all modes) are excited.
Debye Temperature
http://en.wikipedia.org/wiki/Exponential_decay
http://www.britannica.com/EBchecked/topic/154945/decay-constant
http://www.iso.org/iso/catalogue_detail?csnumber=31895
Relative variation \(\frac{dN}{N}\) of the number \(N\) of atoms or nuclei in a system, due to spontaneous emission from these atoms or nuclei during an infinitesimal time interval, divided by its duration \(dt\), thus \(\lambda = -\frac{1}{N}\frac{dN}{dt}\).
\(\lambda\)
The "Decay Constant" is the proportionality between the size of a population of radioactive atoms and the rate at which the population decreases because of radioactive decay.
Decay Constant
http://dbpedia.org/resource/Faraday_constant
http://en.wikipedia.org/wiki/Dissociation_(chemistry)
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(\alpha\)
The "Degree of Dissociation" is the fraction of original solute molecules that have dissociated.
Degree of Dissociation
The mass density or density of a material is defined as its mass per unit volume. The symbol most often used for density is \(\rho\). Mathematically, density is defined as mass divided by volume: \(\rho = m/V\), where \(\rho\) is the density, \(m\) is the mass, and \(V\) is the volume. In some cases, density is also defined as its weight per unit volume, although this quantity is more properly called specific weight.
\(M/L^3\)
\(kg/m^3\)
http://dbpedia.org/resource/Density
http://en.wikipedia.org/wiki/Density
\(\rho = m/V\), where \(\rho\) is the density, \(m\) is the mass, and \(V\) is the volume.
\(\rho\)
belongs to SOQ-ISO
Density
\(\rho_c\)
Density In Combustion Chamber
http://en.wikipedia.org/wiki/Density_of_states
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Density of States" is the number of vibrational modes in an infinitesimal interval of angular frequency divided by the range of that interval and by volume.
g
Density of states
\(\rho\)
Density Of The Exhaust Gases
Depth typically refers to the vertical measure of length from the surface of a liquid.
Depth
http://www.iso.org/iso/catalogue_detail?csnumber=31890
"Dew Point Temperature" is the temperature at which vapour in air reaches saturation.
T_d
Dew Point Temperature
http://dbpedia.org/resource/Diameter
http://en.wikipedia.org/wiki/Diameter
http://www.iso.org/iso/catalogue_detail?csnumber=43012
\(d = 2r\), where \(r\) is the radius of the circle.
In classical geometry, the "Diameter" of a circle is any straight line segment that passes through the center of the circle and whose endpoints lie on the circle.
d
Diameter
http://www.oxfordreference.com/view/10.1093/acref/9780199549351.001.0001/acref-9780199549351-e-1162
The pressure of blood in the arteries which rises to a maximum as blood is pumped out by the left ventricle (systole) and drops to a minimum in diastole. The systolic/diastolic pressure is normally ~120/80 mmHg in a young adult.
Diastolic Blood Pressure
http://encyclopedia2.thefreedictionary.com/diffusion+area
http://www.iso.org/iso/catalogue_detail?csnumber=31895
"Diffusion Area" in an infinite homogenous medium, is one-sixth of the mean square distance between the point where a neutron enters a specified class and the point where it leaves that class.
L^2
Diffusion Area
http://en.wikipedia.org/wiki/Mass_diffusivity
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(C_B \left \langle \nu_B \right \rangle = -D grad C_B\), where \(C_B\) the local molecular concentration of substance \(B\) in the mixture and \(\left \langle \nu_B \right \rangle\) is the local average velocity of the molecules of \(B\).
The "Diffusion Coefficient" is a proportionality constant between the molar flux due to molecular diffusion and the gradient in the concentration of the species (or the driving force for diffusion). Diffusivity is encountered in Fick's law and numerous other equations of physical chemistry.
D
Diffusion Coefficient
m
http://en.wikipedia.org/wiki/Mass_diffusivity
\(D_\varphi = -\frac{J_x}{\frac{\partial d\varphi}{\partial dx}}\), where \(J_x\) is the \(x-component\) of the particle current and \(\varphi\) is the particle fluence rate.
http://www.iso.org/iso/catalogue_detail?csnumber=31895
The "Diffusion Coefficient for Fluence Rate" is a proportionality constant between the .
Dᵩ
Diffusion Coefficient for Fluence Rate
http://encyclopedia2.thefreedictionary.com/diffusion+length
\(L = \sqrt{L^2}\), where \(L^2\) is the diffusion area.
http://www.iso.org/iso/catalogue_detail?csnumber=31895
"Diffusion Length" is the average distance traveled by a particle, or a thermal neutron in a nuclear reactor, from the point at which it is formed to the point at which it is absorbed.
L
Diffusion Length
In dimensional analysis, a dimensionless quantity or quantity of dimension one is a quantity without an associated physical dimension. It is thus a "pure" number, and as such always has a dimension of 1. Dimensionless quantities are widely used in mathematics, physics, engineering, economics, and in everyday life (such as in counting). Numerous well-known quantities, such as \(\pi\), \(\epsilon\), and \(\psi\), are dimensionless. By contrast, non-dimensionless quantities are measured in units of length, area, time, etc. Dimensionless quantities are often defined as products or ratios of quantities that are not dimensionless, but whose dimensions cancel out when their powers are multiplied.
\(U\)
\(\)
http://dbpedia.org/resource/Dimensionless_quantity
http://en.wikipedia.org/wiki/Dimensionless_quantity
U
Dimensionless
Dimensionless Ratio
http://en.wikipedia.org/wiki/Displacement_(vector)
http://www.iso.org/iso/catalogue_detail?csnumber=43012
\(\Delta r = R_f - R_i\), where \(R_f\) is the final position and \(R_i\) is the initial position.
\(\Delta r\)
"Displacement" is the shortest distance from the initial to the final position of a point P.
Displacement
http://en.wikipedia.org/wiki/Displacement_current
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(I_D= \int_S J_D \cdot e_n dA\), over a surface \(S\), where \(J_D\) is displacement current density and \(e_n dA\) is the vector surface element.
"Displacement Current" is a quantity appearing in Maxwell's equations that is defined in terms of the rate of change of electric displacement field. Displacement current has the units of electric current density, and it has an associated magnetic field just as actual currents do. However it is not an electric current of moving charges, but a time-varying electric field. In materials, there is also a contribution from the slight motion of charges bound in atoms, dielectric polarization.
I_D
Displacement Current
\(\textbf{Displacement Current Density}\) is the time rate of change of the \(\textit{Electric Flux Density}\). This is a measure of how quickly the electric field changes if we observe it as a function of time. This is different than if we look at how the electric field changes spatially, that is, over a region of space for a fixed amount of time.
http://dbpedia.org/resource/Electric_flux
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
http://www.maxwells-equations.com/math/partial-electric-flux.php
\(J_D = \frac{\partial D}{\partial t}\), where \(D\) is electric flux density and \(t\) is time.
\(J_D\)
Displacement Current Density
http://en.wikipedia.org/wiki/Displacement
\(u = R - R_0\), where \(R\) is the particle position vector and \(R_0\) is the equilibrium position vector of a particle.
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Displacement Vector of Ion" is the .
u
Displacement Vector of Ion
http://en.wikipedia.org/wiki/Dissipation_factor
\(\delta = \frac{P_d}{P_i}\), where \(P_d\) is the dissipated sound power, and \(P_i\) is the incident sound power.
\(\delta\)
Dissipance, or dissipation factor for sound power, is the ratio of dissipated sound power to incident sound power. The dissipation factor (DF) is a measure of loss-rate of energy of a mode of oscillation (mechanical, electrical, or electromechanical) in a dissipative system. It is the reciprocal of quality factor, which represents the quality of oscillation.
belongs to SOQ-ISO
Dissipance
http://en.wikipedia.org/wiki/Distance
http://www.iso.org/iso/catalogue_detail?csnumber=43012
"Distance" is a numerical description of how far apart objects are.
d
Distance
s
Distance Traveled During a Burn
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Donor Density" is the number per volume of donor levels.
n_d
Donor Density
http://en.wikipedia.org/wiki/Ionization_energy
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Donor Ionization Energy" is the ionization energy of a donor.
E_d
Donor Ionization Energy
"Dose Equivalent} (former), or \textit{Equivalent Absorbed Radiation Dose}, usually shortened to \textit{Equivalent Dose", is a computed average measure of the radiation absorbed by a fixed mass of biological tissue, that attempts to account for the different biological damage potential of different types of ionizing radiation. The equivalent dose to a tissue is found by multiplying the absorbed dose, in gray, by a dimensionless "quality factor" \(Q\), dependent upon radiation type, and by another dimensionless factor \(N\), dependent on all other pertinent factors. N depends upon the part of the body irradiated, the time and volume over which the dose was spread, even the species of the subject.
http://dbpedia.org/resource/Equivalent_dose
http://en.wikipedia.org/wiki/Equivalent_dose
http://www.iso.org/iso/catalogue_detail?csnumber=31895
At the point of interest in tissue, \(H = DQ\), where \(D\) is the absorbed dose and \(Q\) is the quality factor at that point.
H
Dose Equivalent
http://en.wikipedia.org/wiki/Equivalent_dose
http://www.iso.org/iso/catalogue_detail?csnumber=31895
"Dose Equivalent Quality Factor" is a factor in the caculation and measurement of dose equivalent, by which the absorbed dose is to be weighted in order to account for different biological effectiveness of radiations, for radiation protection purposes.
Q
Dose Equivalent Quality Factor
In fluid dynamics, the drag coefficient is a dimensionless quantity that is used to quantify the drag or resistance of an object in a fluid environment such as air or water.
C_D
Drag Coefficient
In fluid dynamics, drag refers to forces which act on a solid object in the direction of the relative fluid flow velocity. Unlike other resistive forces such as dry friction, which is nearly independent of velocity, drag forces depend on velocity.
Drag forces always decrease fluid velocity relative to the solid object in the fluid's path.
D or F_D
Drag Force
Dry measures are units of volume used to measure bulk commodities which are not gas or liquid. They are typically used in agriculture, agronomy, and commodity markets to measure grain, dried beans, and dried and fresh fruit; formerly also salt pork and fish. They are also used in fishing for clams, crabs, etc. and formerly for many other substances (for example coal, cement, lime) which were typically shipped and delivered in a standardized container such as a barrel. In the original metric system, the unit of dry volume was the stere, but this is not part of the modern metric system; the liter and the cubic meter (\(m^{3}\)) are now used. However, the stere is still widely used for firewood.
http://en.wikipedia.org/wiki/Dry_measure
Dry Volume
http://dbpedia.org/resource/Friction
http://en.wikipedia.org/wiki/Friction
http://www.iso.org/iso/catalogue_detail?csnumber=31889
Kinetic (or dynamic) friction occurs when two objects are moving relative to each other and rub together (like a sled on the ground).
Dynamic Friction
http://dbpedia.org/resource/Friction
http://en.wikipedia.org/wiki/Friction
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(\mu = \frac{F}{N}\), where \(F\) is the tangential component of the contact force and \(N\) is the normal component of the contact force between two sliding bodies.
\(\mu\)
Kinetic (or dynamic) friction occurs when two objects are moving relative to each other and rub together (like a sled on the ground).
Dynamic Friction Coefficient
Dynamic Pressure (indicated with q, or Q, and sometimes called velocity pressure) is the quantity defined by: \(q = 1/2 * \rho v^{2}\), where (using SI units), \(q\) is dynamic pressure in \(pascals\), \(\rho\) is fluid density in \(kg/m^{3}\) (for example, density of air) and \(v \) is fluid velocity in \(m/s\).
http://dbpedia.org/resource/Dynamic_pressure
q
Dynamic Pressure
\(M/L \cdot T\)
\(kg/m \cdot s\)
http://dictionary.reference.com/browse/dynamic+viscosity
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(\tau_{xz} = \eta\frac{dv_x}{dz}\), where \(\tau_{xz}\) is shear stress in a fluid moving with a velocity gradient \(\frac{dv_x}{dz}\) perpendicular to the plane of shear.
\(\mu\)
A measure of the molecular frictional resistance of a fluid as calculated using Newton's law.
Dynamic Viscosity
V_o
Earth Closest Approach Vehicle Velocity
\(\varepsilon\)
The orbital eccentricity of an astronomical object is a parameter that determines the amount by which its orbit around another body deviates from a perfect circle. In a two-body problem with inverse-square-law force, every orbit is a Kepler orbit. The eccentricity of this Kepler orbit is a positive number that defines its shape.
Eccentricity Of Orbit
The velocity of an exhaust stream after reduction by effects such as friction, non-axially directed flow, and pressure differences between the inside of the rocket and its surroundings. The effective exhaust velocity is one of two factors determining the thrust, or accelerating force, that a rocket can develop, the other factor being the quantity of reaction mass expelled from the rocket in unit time. In most cases, the effective exhaust velocity is close to the actual exhaust velocity.
v_{e}
Effective Exhaustvelocity
http://en.wikipedia.org/wiki/Effective_mass_(solid-state_physics)
http://www.iso.org/iso/catalogue_detail?csnumber=31897
\(m^* = \hbar^2k(\frac{d\varepsilon}{dk})\), where \(\hbar\) is the reduced Planck constant, \(k\) is the wavenumber, and \(\varepsilon\) is the energy of the electron.
"Effective Mass" is used in the motional equation for electrons in solid state bodies, depending on the wavenumber and corresponding to its velocity and energy level.
m^*
Effective Mass
http://en.wikipedia.org/wiki/Nuclear_chain_reaction#Effective_neutron_multiplication_factor
http://www.iso.org/iso/catalogue_detail?csnumber=31895
The "Effective Multiplication Factor" is the multiplication factor for a finite medium.
k_{eff}
Effective Multiplication Factor
http://en.wikipedia.org/wiki/Deformation_(mechanics)
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(\eta = \frac{P_{out}}{P_{in}}\), where \(P_{out}\) is the output power and \(P_{in}\) is the input power.
\(\eta\)
Efficiency is the ratio of output power to input power.
Efficiency
Given two atomic states of energy \(E_j\) and \(E_k\). Let \(E_j > E_k\). Assume the atom is bathed in radiation of energy density \(u(w)\). Transitions between these states can take place in three different ways. Spontaneous, induced/stimulated emission, and induced absorption. \(A_jk\) represents the Einstein transition probability for spontaneous emission.
\(\frac{-dN_j}{dt} = A_jkN_j\), where \(-dN_j\) is the number of molecules spontaneously leaving the state j for the state k during a time interval of duration \(dt\), \(N_j\) is the number of molecules in the state j, and \(E_j > E_k\).
A_jkN_j
Einstein Transition Probability
"Electric Charge" is a fundamental conserved property of some subatomic particles, which determines their electromagnetic interaction. Electrically charged matter is influenced by, and produces, electromagnetic fields. The electric charge on a body may be positive or negative. Two positively charged bodies experience a mutual repulsive force, as do two negatively charged bodies. A positively charged body and a negatively charged body experience an attractive force. Electric charge is carried by discrete particles and can be positive or negative. The sign convention is such that the elementary electric charge \(e\), that is, the charge of the proton, is positive. The SI derived unit of electric charge is the coulomb.
\(A \cdot s\)
\(I \cdot T\)
http://en.wikipedia.org/wiki/Electric_charge
http://en.wikipedia.org/wiki/Electric_charge?oldid=492961669
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(dQ = Idt\), where \(I\) is electric current.
Q
Electric Charge
\(charge-density\)
http://en.wikipedia.org/wiki/Charge_density
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
http://www.maxwells-equations.com/pho/charge-density.php
\(\rho = \frac{dQ}{dV}\), where \(Q\) is electric charge and \(V\) is Volume.
\(\rho\)
In electromagnetism, charge density is a measure of electric charge per unit volume of space, in one, two or three dimensions. More specifically: the linear, surface, or volume charge density is the amount of electric charge per unit length, surface area, or volume, respectively.
Electric Charge Density
In electromagnetism, charge density is a measure of electric charge per unit volume of space, in one, two or three dimensions. More specifically: the linear, surface, or volume charge density is the amount of electric charge per unit length, surface area, or volume, respectively. The respective SI units are \(C \cdot \), \(m^{-1}\), \(C \cdot m^{-2}\) or \(C \cdot m^{-3}\).
\(A \cdot s/m\)
\(I \cdot T/L\)
http://en.wikipedia.org/wiki/Charge_density
\(\lambda\)
Electric Charge Line Density
\(linear-charge-density\)
http://en.wikipedia.org/wiki/Charge_density
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(\rho_l = \frac{dQ}{dl}\), where \(Q\) is electric charge and \(l\) is length.
\(\rho_l\)
\(\tau\)
In electromagnetism, charge density is a measure of electric charge per unit volume of space, in one, two or three dimensions. More specifically: the linear, surface, or volume charge density is the amount of electric charge per unit length, surface area, or volume, respectively.
Electric Charge Linear Density
"Electric Charge Per Amount Of Substance" is the charge assocated with a given amount of substance. Un the ISO and SI systems this is \(1 mol\).
\(A \cdot s/mol\)
\(I \cdot T/M\)
Electric charge per amount of substance
In electromagnetism, charge density is a measure of electric charge per unit volume of space, in one, two or three dimensions. More specifically: the linear, surface, or volume charge density is the amount of electric charge per unit length, surface area, or volume, respectively. The respective SI units are \(C \cdot m^{-1}\), \(C \cdot m^{-2}\) or \(C \cdot m^{-3}\).
\(A \cdot s/m^2\)
\(I \cdot T/L^2\)
http://en.wikipedia.org/wiki/Charge_density
\(\sigma\)
Electric charge per area
"Electric Charge Per Mass" is the charge associated with a specific mass of a substance. In the SI and ISO systems this is \(1 kg\).
\(A \cdot s/kg\)
\(I \cdot T/M\)
Electric Charge Per Mass
\(surface-charge-density\)
http://en.wikipedia.org/wiki/Charge_density
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(\rho_A = \frac{dQ}{dA}\), where \(Q\) is electric charge and \(A\) is Area.
\(\rho_A\)
In electromagnetism, charge density is a measure of electric charge per unit volume of space, in one, two or three dimensions. More specifically: the linear, surface, or volume charge density is the amount of electric charge per unit length, surface area, or volume, respectively.
Electric Charge Surface Density
In electromagnetism, charge density is a measure of electric charge per unit volume of space, in one, two or three dimensions. More specifically: the linear, surface, or volume charge density is the amount of electric charge per unit length, surface area, or volume, respectively. The respective SI units are \(C \cdot m^{-1}\), \(C \cdot m^{-2}\) or \(C \cdot m^{-3}\).
\(A \cdot s/m^3\)
\(I \cdot T/L^3\)
http://en.wikipedia.org/wiki/Charge_density
\(\rho\)
Electric Charge Volume Density
"Electric Conductivity} or \textit{Specific Conductance" is a measure of a material's ability to conduct an electric current. When an electrical potential difference is placed across a conductor, its movable charges flow, giving rise to an electric current. The conductivity \(\sigma\) is defined as the ratio of the electric current density \(J\) to the electric field \(E\): \(J = \sigma E\). In isotropic materials, conductivity is scalar-valued, however in general, conductivity is a tensor-valued quantity.
\(A^2 \cdot s^3/kg \cdot m^2\)
\(I^2 \cdot T^3/L^2 \cdot M\)
\(\sigma\)
Electric Conductivity
\(A\)
\(I\)
http://dbpedia.org/resource/Electric_current
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
"Electric Current" is the flow (movement) of electric charge. The amount of electric current through some surface, for example, a section through a copper conductor, is defined as the amount of electric charge flowing through that surface over time. Current is a scalar-valued quantity. Electric current is one of the base quantities in the International System of Quantities, ISQ, on which the International System of Units, SI, is based.
I
Electric Current
"Electric Current Density" is a measure of the density of flow of electric charge; it is the electric current per unit area of cross section. Electric current density is a vector-valued quantity. Electric current, \(I\), through a surface \(S\) is defined as \(I = \int_S J \cdot e_n dA\), where \(e_ndA\) is the vector surface element.
\(A/m^2\)
\(I/L^2\)
http://dbpedia.org/resource/Current_density
http://maxwells-equations.com/density/current.php
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(J = \rho v\), where \(\rho\) is electric current density and \(v\) is volume.
J
Electric Current Density
\(A\)
\(I/U\)
Electric Current per Angle
\(A \cdot s^3/kg \cdot m^2\)
\(I \cdot T^3/L^2 \cdot M\)
Electric Current per Unit Energy
\(A/m\)
\(I/L\)
Electric Current per Unit Length
"Electric Current per Unit Temperature" is used to express how a current is subject to temperature. Originally used in Wien's Law to describe phenomena related to filaments. One use today is to express how a current generator derates with temperature.
Electric Current per Unit Temperature
http://en.wikipedia.org/wiki/Phasor_(electronics)
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=131-11-26
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
When \(i = \hat{I} \cos{(\omega t + \alpha)}\), where \(i\) is the electric current, \(\omega\) is angular frequence, \(t\) is time, and \(\alpha\) is initial phase, then \(\underline{I} = Ie^{ja}\).
\(\underline{I}\)
"Electric Current Phasor" is a representation of current as a sinusoidal integral quantity using a complex quantity whose argument is equal to the initial phase and whose modulus is equal to the root-mean-square value. A phasor is a constant complex number, usually expressed in exponential form, representing the complex amplitude (magnitude and phase) of a sinusoidal function of time. Phasors are used by electrical engineers to simplify computations involving sinusoids, where they can often reduce a differential equation problem to an algebraic one.
Electric Current Phasor
\(A \cdot m \cdot s\)
\(I \cdot L \cdot T\)
http://en.wikipedia.org/wiki/Electric_dipole_moment
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(E_p = -p \cdot E\), where \(E_p\) is the interaction energy of the molecule with electric dipole moment \(p\) and an electric field with electric field strength \(E\).
\(p = q(r_+ - r_i)\), where \(r_+\) and \(r_-\) are the position vectors to carriers of electric charge \(a\) and \(-q\), respectively.
"Electric Dipole Moment" is a measure of the separation of positive and negative electrical charges in a system of (discrete or continuous) charges. It is a vector-valued quantity. If the system of charges is neutral, that is if the sum of all charges is zero, then the dipole moment of the system is independent of the choice of a reference frame; however in a non-neutral system, such as the dipole moment of a single proton, a dependence on the choice of reference point arises. In such cases it is conventional to choose the reference point to be the center of mass of the system or the center of charge, not some arbitrary origin. This convention ensures that the dipole moment is an intrinsic property of the system. The electric dipole moment of a substance within a domain is the vector sum of electric dipole moments of all electric dipoles included in the domain.
p
Electric Dipole Moment
In a dielectric material the presence of an electric field E causes the bound charges in the material (atomic nuclei and their electrons) to slightly separate, inducing a local electric dipole moment. The Electric Displacement Field, \(D\), is a vector field that accounts for the effects of free charges within such dielectric materials. This describes also the charge density on an extended surface that could be causing the field.
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
http://www.oxfordreference.com/view/10.1093/acref/9780199233991.001.0001/acref-9780199233991-e-895
\(D = \epsilon_0 E + P\), where \(\epsilon_0\) is the electric constant, \(E\) is electric field strength, and \(P\) is electric polarization.
D
Electric Displacement
D
Electric Displacement Field
\(L \cdot M/I \cdot T^3\)
\(kg \cdot m/A \cdot s^3\)
http://dbpedia.org/resource/Electric_field
\(E\)
http://en.wikipedia.org/wiki/Electric_field
The space surrounding an electric charge or in the presence of a time-varying magnetic field has a property called an electric field. This electric field exerts a force on other electrically charged objects. In the idealized case, the force exerted between two point charges is inversely proportional to the square of the distance between them. (Coulomb's Law).
Electric Field
\(\textbf{Electric Field Strength}\) is the magnitude and direction of an electric field, expressed by the value of \(E\), also referred to as \(\color{indigo} {\textit{electric field intensity}}\) or simply the electric field.
\(kg \cdot m/A \cdot s^3\)
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(\mathbf{E} = \mathbf{F}/q\), where \(\mathbf{F}\) is force and \(q\) is electric charge, of a test particle at rest.
\(\mathbf{E} \)
E
Electric Field Strength
\(L^3 \cdot M/I \cdot T^3\)
\(kg \cdot m^3/A \cdot s^3\)
http://dbpedia.org/resource/Electric_flux
\(electirc-flux\)
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(\Psi = \int_S D \cdot e_n dA\), over a surface \(S\), where \(D\) is electric flux density and \(e_n dA\) is the vector surface element.
\(\Psi\)
"Electric Flux" through an area is defined as the electric field multiplied by the area of the surface projected in a plane perpendicular to the field. Electric Flux is a scalar-valued quantity.
Electric Flux
\(\textbf{Electric Flux Density}\), also referred to as \(\textit{Electric Displacement}\), is related to electric charge density by the following equation: \(\text{div} \; D = \rho\), where \(\text{div}\) denotes the divergence.
http://dbpedia.org/resource/Electric_flux
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(\mathbf{D} = \epsilon_0 E + P\), where \(\epsilon_0\) is the electric constant, \(\mathbf{E} \) is electric field strength, and \(P\) is electric polarization.
\(\mathbf{D}\)
Electric Flux Density
http://en.wikipedia.org/wiki/Polarizability
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(\alpha_{i,j} = \frac{\partial p_i}{\partial E_j}\), where \(p_i\) is the cartesian component along the \(i-axis\) of the electric dipole moment induced by the applied electric field strength acting on the molecule, and \(E_j\) is the component along the \(j-axis\) of this electric field strength.
\(\alpha\)
"Electric Polarizability" is the relative tendency of a charge distribution, like the electron cloud of an atom or molecule, to be distorted from its normal shape by an external electric field, which is applied typically by inserting the molecule in a charged parallel-plate capacitor, but may also be caused by the presence of a nearby ion or dipole.
Electric Polarizability
http://www.britannica.com/EBchecked/topic/182690/electric-polarization
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(P =\frac{dp}{dV}\), where \(p\) is electic charge density and \(V\) is volume.
"Electric Polarization" is the relative shift of positive and negative electric charge in opposite directions within an insulator, or dielectric, induced by an external electric field. Polarization occurs when an electric field distorts the negative cloud of electrons around positive atomic nuclei in a direction opposite the field. This slight separation of charge makes one side of the atom somewhat positive and the opposite side somewhat negative. In some materials whose molecules are permanently polarized by chemical forces, such as water molecules, some of the polarization is caused by molecules rotating into the same alignment under the influence of the electric field. One of the measures of polarization is electric dipole moment, which equals the distance between the slightly shifted centres of positive and negative charge multiplied by the amount of one of the charges. Polarization P in its quantitative meaning is the amount of dipole moment p per unit volume V of a polarized material, P = p/V.
P
Electric Polarization
The Electric Potential is a scalar valued quantity associated with an electric field. The electric potential \(\phi(x)\) at a point, \(x\), is formally defined as the line integral of the electric field taken along a path from x to the point at infinity. If the electric field is static, that is time independent, then the choice of the path is arbitrary; however if the electric field is time dependent, taking the integral a different paths will produce different results.
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
http://www.iso.org/iso/catalogue_detail?csnumber=43012
\(-\textbf{grad} \; V = E + \frac{\partial A}{\partial t}\), where \(E\) is electric field strength, \(A\) is magentic vector potential and \(t\) is time.
\(\phi\)
V
Electric Potential
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(V_{ab} = \int_{r_a(C)}^{r_b} (E +\frac{\partial A}{\partial t}) \), where \(E\) is electric field strength, \(A\) is magentic vector potential, \(t\) is time, and \(r\) is position vector along a curve C from a point \(a\) to \(b\).
"Electric Potential Difference" is a scalar valued quantity associated with an electric field.
V_{ab}
Electric Potential Difference
"Electric Power" is the rate at which electrical energy is transferred by an electric circuit. In the simple case of direct current circuits, electric power can be calculated as the product of the potential difference in the circuit (V) and the amount of current flowing in the circuit (I): \(P = VI\), where \(P\) is the power, \(V\) is the potential difference, and \(I\) is the current. However, in general electric power is calculated by taking the integral of the vector cross-product of the electrical and magnetic fields over a specified area.
\(p = ui\), where \(u\) is instantaneous voltage and \(i\) is instantaneous electric current.
P_E
Electric Power
M_P
Electric Propulsion Propellant Mass
\(A \cdot m^2 \cdot s\)
\(I \cdot L^2 \cdot T\)
The Electric Quadrupole Moment is a quantity which describes the effective shape of the ellipsoid of nuclear charge distribution. A non-zero quadrupole moment Q indicates that the charge distribution is not spherically symmetric. By convention, the value of Q is taken to be positive if the ellipsoid is prolate and negative if it is oblate. In general, the electric quadrupole moment is tensor-valued.
Q
Electric Quadrupole Moment
http://dbpedia.org/resource/Permittivity
\(e-susceptibility\)
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(\chi = \frac{P}{(\epsilon_0 E)}\), where \(P\) is electric polorization, \(\epsilon_0\) is the electric constant, and \(E\) is electric field strength.
\(\chi\)
"Electric Susceptibility" is the ratio of electric polarization to electric field strength, normalized to the electric constant. The definition applies to an isotropic medium. For an anisotropic medium, electric susceptibility is a second order tensor.
Electric Susceptibility
\(\xi\)
Electrical Power To Mass Ratio
http://en.wikipedia.org/wiki/Conductivity_(electrolytic)
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(x = \frac{J}{E}\), where \(J\) is the electrolytic current density and \(E\) is the electric field strength.
"Electrolytic Conductivity" of an electrolyte solution is a measure of its ability to conduct electricity.
x
Electrolytic Conductivity
\(\textbf{Electromagnetic Energy Density}\), also known as the \(\color{indigo} {\textit{Volumic Electromagnetic Energy}}\), is the energy associated with an electromagnetic field, per unit volume of the field.
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=121-11-64
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(w = (1/2) ( \mathbf{E} \cdot \mathbf{D} + \mathbf{B} \cdot \mathbf{H})\), where \(\mathbf{E}\) is electric field strength, \(\mathbf{D}\) is electric flux density, \(\mathbf{M}\) is magnetic flux density, and \(\mathbf{H}\) is magnetic field strength.
w
Electromagnetic Energy Density
"Permeability} is the degree of magnetization of a material that responds linearly to an applied magnetic field. In general permeability is a tensor-valued quantity. The definition given applies to an isotropic medium. For an anisotropic medium permeability is a second order tensor. In electromagnetism, permeability is the measure of the ability of a material to support the formation of a magnetic field within itself. In other words, it is the degree of magnetization that a material obtains in response to an applied magnetic field. Magnetic permeability is typically represented by the Greek letter \(\mu\). The term was coined in September, 1885 by Oliver Heaviside. The reciprocal of magnetic permeability is \textit{Magnetic Reluctivity".
\(L \cdot M/I^2 \cdot T^2\)
\(kg \cdot m/A^2 \cdot s^2\)
http://dbpedia.org/resource/Permeability
http://en.wikipedia.org/wiki/Permeability_(electromagnetism)
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(\mu = \frac{B}{H}\), where \(B\) is magnetic flux density, and \(H\) is magnetic field strength.
\(\mu\)
Permeability
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
The ratio of the electromagnetic permeability of a specific medium to the electromagnetic permeability of free space.
Electromagnetic Permeability Ratio
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=121-11-66
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(c = w/k\) where \(w\) is angular velocity and \(k\) is angular wavenumber.
"Electromagnetic Wave Phase Speed" is the ratio of angular velocity and wavenumber.
c
Electromagnetic Wave Phase Speed
In physics, electromotive force, or most commonly \(emf\) (seldom capitalized), or (occasionally) electromotance is that which tends to cause current (actual electrons and ions) to flow. More formally, \(emf\) is the external work expended per unit of charge to produce an electric potential difference across two open-circuited terminals. "Electromotive Force" is deprecated in the ISO System of Quantities.
http://dbpedia.org/resource/Electromotive_force
E
Electromotive Force
http://en.wikipedia.org/wiki/Electron_affinity
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Electron Affinity" is the energy difference between an electron at rest at infinity and an electron at the lowest level of the conduction band in an insulator or semiconductor. The the amount of energy released when an electron is added to a neutral atom or molecule to form a negative ion.
χ
Electron Affinity
http://en.wikipedia.org/wiki/Electron_density
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Electron Density" is the number of electrons per volume in conduction bands. It is the measure of the probability of an electron being present at a specific location.
n
Electron Density
http://en.wikipedia.org/wiki/Thermal_conductivity
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Electron Mean Free Path" is the mean free path of electrons.
l_e
Electron Mean Free Path
http://en.wikipedia.org/wiki/Classical_electron_radius
\(r_e = \frac{e^2}{4\pi m_e c_0^2}\), where \(e\) is the elementary charge, \(\varepsilon_0\) is the electric constant, item \(m_e\) is the rest mass of electrons, and \(c_0\) is the speed of light in vacuum.
http://www.iso.org/iso/catalogue_detail?csnumber=31895
"Electron Radius", also known as the Lorentz radius or the Thomson scattering length, is based on a classical (i.e., non-quantum) relativistic model of the electron.
r_e
Electron Radius
http://en.wikipedia.org/wiki/Elementary_charge
http://www.iso.org/iso/catalogue_detail?csnumber=31894
The "Elementary Charge" is the electric charge carried by a single proton, or equivalently, the negation (opposite) of the electric charge carried by a single electron.
e
Elementary Charge
Velocity at apogee for an elliptical orbit velocity
V_a
Elliptical Orbit Apogee Velocity
Velocity at apogee for an elliptical orbit velocity.
V_p
Elliptical Orbit Perigee Velocity
Emissivity of a material (usually written \(\varepsilon\) or e) is the relative ability of its surface to emit energy by radiation.
\(\varepsilon = \frac{M}{M_b}\), where \(M\) is the radiant exitance of a thermal radiator and \(M_b\) is the radiant exitance of a blackbody at the same temperature.
\(\varepsilon\)
Emissivity
http://dbpedia.org/resource/Energy
http://www.iso.org/iso/catalogue_detail?csnumber=31890
Energy is the quantity characterizing the ability of a system to do work.
E
Energy
\(m^{-1} \cdot kg \cdot s^{-2}\)
\(ft^{-1} \cdot lb \cdot s^{-2}\)
\(m^{-1} \cdot kg \cdot s^{-2}\)
\(L^{-1} \cdot M \cdot T^{-2}\)
http://dbpedia.org/resource/Energy_density
http://en.wikipedia.org/wiki/Energy_density
Energy density is defined as energy per unit volume. The SI unit for energy density is the joule per cubic meter.
Energy Density
http://en.wikipedia.org/wiki/Density_of_states
http://www.iso.org/iso/catalogue_detail?csnumber=31897
\(\rho(E) = n_E(E) = \frac{dN(E)}{dE}\frac{1}{V}\), where \(N(E)\) is the total number of states with energy less than \(E\), and \(V\) is the volume.
"Energy Density of States" refers to electrons or other entities, e.g. phonons. It can, for example, refer to amount of substance instead of volume.
n_E
Energy Density of States
Energy expenditure is dependent on a person's sex, metabolic rate, body-mass composition, the thermic effects of food, and activity level. The approximate energy expenditure of a man lying in bed is \(1.0\,kilo\,calorie\,per\,hour\,per\,kilogram\). For slow walking (just over two miles per hour), \(3.0\,kilo\,calorie\,per\,hour\,per\,kilogram\). For fast steady running (about 10 miles per hour), \(16.3\,kilo\,calorie\,per\,hour\,per\,kilogram\).
Females expend about 10 per cent less energy than males of the same size doing a comparable activity. For people weighing the same, individuals with a high percentage of body fat usually expend less energy than lean people, because fat is not as metabolically active as muscle.
http://www.oxfordreference.com/view/10.1093/acref/9780198631477.001\).0001/acref-9780198631477-e-594
Energy Expenditure
http://en.wikipedia.org/wiki/Fluence
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(\Psi = \frac{dR}{dA}\), where \(dR\) describes the sum of radiant energies, exclusive of rest energy, of all particles incident on a small spherical domain, and \(dA\) describes the cross-sectional area of that domain.
\(\Psi\)
"Energy Fluence" can be used to describe the energy delivered per unit area
Energy Fluence
http://en.wikipedia.org/wiki/Fluence
\(\Psi = \frac{d\Psi}{dt}\), where \(d\Psi\) is the increment of the energy fluence during an infinitesimal time interval with duration \(dt\).
http://www.iso.org/iso/catalogue_detail?csnumber=31895
"Energy Fluence Rate" can be used to describe the energy fluence delivered per unit time.
Ψ
Energy Fluence Rate
http://www.answers.com/topic/energy-imparted
For ionizing radiation in the matter in a given 3D domain, \(\varepsilon = \sum_i \varepsilon_i\), where the energy deposit, \(\varepsilon_i\) is the energy deposited in a single interaction \(i\), and is given by \(\varepsilon_i = \varepsilon_{in} - \varepsilon_{out} + Q\), where \(\varepsilon_{in}\) is the energy of the incident ionizing particle, excluding rest energy, \(\varepsilon_{out}\) is the sum of the energies of all ionizing particles leaving the interaction, excluding rest energy, and \(Q\) is the change in the rest energies of the nucleus and of all particles involved in the interaction.
http://www.iso.org/iso/catalogue_detail?csnumber=31895
The "Energy Imparted", is a physical quantity associated with the energy delivered to a particular volume of matter by all the directly and indirectly ionizing particles (i.e. charged and uncharged) entering that volume.
ε
Energy Imparted
The internal energy is the total energy contained by a thermodynamic system. It is the energy needed to create the system, but excludes the energy to displace the system's surroundings, any energy associated with a move as a whole, or due to external force fields. Internal energy has two major components, kinetic energy and potential energy. The internal energy (U) is the sum of all forms of energy (Ei) intrinsic to a thermodynamic system: \( U = \sum_i E_i \)
http://dbpedia.org/resource/Internal_energy
http://en.wikipedia.org/wiki/Internal_energy
http://wiki.answers.com/Q/What_is_the_one_letter_symbol_for_energy
E
Internal Energy
http://dbpedia.org/resource/Kinetic_energy
http://en.wikipedia.org/wiki/Kinetic_energy
The kinetic energy of an object is the energy which it possesses due to its motion. It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity.
Kinetic Energy
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Energy Level" is the ionization energy for an electron at the Fermi energy in the interior of a substance.
E
Energy Level
\(M/T^2\)
\(kg/s^2\)
http://www.calculator.org/property.aspx?name=energy%20per%20unit%20area
Energy per unit area is a measure of the energy either impinging upon or generated from a given unit of area. This can be a measure of the "toughness" of a material, being the amount of energy that needs to be applied per unit area of a crack to cause it to fracture. This is a constant for a given material..
Energy per Area
\(M/I \cdot T^3\)
\(kg/A \cdot s^3\)
"Energy Per Area Electric Charge" is the amount of electric energy associated with a unit of area.
Energy Per Area Electric Charge
Voltage is a representation of the electric potential energy per unit charge. If a unit of electrical charge were placed in a location, the voltage indicates the potential energy of it at that point. In other words, it is a measurement of the energy contained within an electric field, or an electric circuit, at a given point. Voltage is a scalar quantity. The SI unit of voltage is the volt, such that \(1 volt = 1 joule/coulomb\).
\(L^2 \cdot M/I \cdot T^3\)
\(kg \cdot m^2/A \cdot s^3\)
http://physics.about.com/od/glossary/g/voltage.htm
V
Energy per electric charge
Energy and work per mass amount of substance
\(A^2 \cdot m^2 \cdot s^2/kg\)
\(I^2 \cdot L^2 \cdot T^2/M\)
"Energy Per Square Magnetic Flux Density" is a measure of energy for a unit of magnetic flux density.
Energy Per Square Magnetic Flux Density
\(L^2 \cdot M/\Theta \cdot T^2\)
\(kg \cdot m^2/K \cdot s^2\)
Energy per temperature
In thermodynamics, \(\textit{enthalpy}\) is the sum of the internal energy \(U\) and the product of pressure \(p\) and volume \(V\) of a system. The characteristic function (also known as thermodynamic potential) \(\textit{enthalpy}\) used to be called \(\textit{heat content}\), which is why it is conventionally indicated by \(H\). The specific enthalpy of a working mass is a property of that mass used in thermodynamics, defined as \(h=u+p \cdot v\), where \(u\) is the specific internal energy, \(p\) is the pressure, and \(v\) is specific volume. In other words, \(h = H / m\) where \(m\) is the mass of the system. The SI unit for \(\textit{Specific Enthalpy}\) is \(\textit{joules per kilogram}\)
http://dbpedia.org/resource/Enthalpy
http://en.citizendium.org/wiki/Enthalpy
http://en.wikipedia.org/wiki/Enthalpy
\(H = U + pV\), where \(U\) is internal energy, \(p\) is pressure and \(V\) is volume.
http://www.iso.org/iso/catalogue_detail?csnumber=31890
H
Enthalpy
When a small amount of heat \(dQ\) is received by a system whose thermodynamic temperature is \(T\), the entropy of the system increases by \(dQ/T\), provided that no irreversible change takes place in the system.
http://dbpedia.org/resource/Entropy
http://www.iso.org/iso/catalogue_detail?csnumber=31890
S
Entropy
http://en.wikipedia.org/wiki/Equilibrium_constant
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(K^\Theta = \Pi_B(\lambda_B^\Theta)^{-\nu_B}\), where \(\Pi_B\) denotes the product for all substances \(B\), \(\lambda_B^\Theta\) is the standard absolute activity of substance \(B\), and \(\nu_B\) is the stoichiometric number of the substance \(B\).
\(K^\Theta\)
The "Equlilbrium Constant", also known as the thermodynamic equilibrium constant, is an expression that gives us a ratio of the products and reactants of a reaction at equilibrium with respect to a specific unit.
Equilibrium Constant
http://en.wikipedia.org/wiki/Equilibrium_constant
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(K_c = \Pi_B(c_B)^{-\nu_B}\), for solutions
\(K_c\)
The "Equlilbrium Constant", also known as the thermodynamic equilibrium constant, is an expression that gives us a ratio of the products and reactants of a reaction at equilibrium with respect to a specific unit.
The unit is unit:MOL-PER-M3 raised to the N where N is the summation of stoichiometric numbers. I don't know what to do with this.
Equilibrium Constant on Concentration Basis
http://en.wikipedia.org/wiki/Equilibrium_constant
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(K_p = \Pi_B(p_B)^{-\nu_B}\), for gases
\(K_p\)
The "Equlilbrium Constant", also known as the thermodynamic equilibrium constant, is an expression that gives us a ratio of the products and reactants of a reaction at equilibrium with respect to a specific unit.
Equilibrium Constant on Pressure Basis
http://en.wikipedia.org/wiki/Position_(vector)
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Equilibrium Position Vector of Ion" is the position vector of a particle in equilibrium.
R_0
Equilibrium Position Vector of Ion
m2
http://www.rockfon.co.uk/acoustics/comparing+ceilings/sound+absorption/equivalent+absorption+area
In a diffuse sound field, the Equivalent Absorption Area is that area of a surface having an absorption factor equal to 1, which, if diffraction effects are neglected, would, in the same diffuse sound field, absorb the same power.
A
belongs to SOQ-ISO
Equivalent absorption area
http://www.iso.org/iso/catalogue_detail?csnumber=43012
\(\Phi_e\)
"Evaporative Heat Transfer" is
Evaporative Heat Transfer
http://www.iso.org/iso/catalogue_detail?csnumber=43012
"Evaporative Heat Transfer Coefficient" is the areic heat transfer coefficient multiplied by the water vapor pressure difference between skind and the environment, and by the exchange area.
h_e
Combined Non Evaporative Heat Transfer Coefficient
http://en.wikipedia.org/wiki/Exchange_interaction
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Exchange Integral" is the constituent of the interaction energy between the spins of adjacent electrons in matter arising from the overlap of electron state functions.
K
Exchange Integral
Exhaust Gas Mean Molecular Weight
Specific heat of exhaust gases at constant pressure.
c_p
Exhaust Gases Specific Heat
\(\rho\)
Exhaust Stream Power
Cross-sectional area at exit plane of nozzle
A_{e}
Exit Plane Cross-sectional Area
p_{e}
Exit Plane Pressure
T_e
Exit Plane Temperature
Expansion Ratio
http://dbpedia.org/resource/Exposure
http://en.wikipedia.org/wiki/Exposure_%28photography%29
http://hps.org/publicinformation/ate/faqs/gammaandexposure.html
http://www.iso.org/iso/catalogue_detail?csnumber=31895
For X-or gamma radiation, \(X = \frac{dQ}{dm}\), where \(dQ\) is the absolute value of the mean total electric charge of the ions of the same sign produced in dry air when all the electrons and positrons liberated or created by photons in an element of air are completely stopped in air, and \(dm\) is the mass of that element.
"Exposure" reflects the extent of ionization events taking place when air is irradiated by ionizing photons (gamma radiation and/or x rays). In photography, exposure is the amount of light allowed to fall on each area unit of a photographic medium (photographic film or image sensor) during the process of taking a photograph. Exposure is measured in lux seconds, and can be computed from exposure value (EV) and scene luminance in a specified region.
X
Exposure
http://hps.org/publicinformation/ate/faqs/gammaandexposure.html
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(\dot{X} = \frac{dX}{dt}\), where \(X\) is the increment of exposure during time interval with duration \(t\).
\(\dot{X}\)
"Exposure Rate" expresses the rate of charge production per unit mass of air and is commonly expressed in roentgens per hour (R/h) or milliroentgens per hour (mR/h).
Exposure Rate
http://en.wikipedia.org/wiki/Extent_of_reaction
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(dn_B = \nu_B d\xi\), where \(n_B\) is the amount of substance \(B\) and \(\nu_B\) is the stoichiometric number of substance \(B\).
\(\xi\)
In physical chemistry, the "Extent of Reaction" is a quantity that measures the extent in which the reaction proceeds.
Extent of Reaction
A quantity of propellant, at a nominal mixture ratio, along with fuel bias that is set aside from total propellant loaded to cover for statistical variations of flight hardware characteristics and environment conditions on the day of launch. The launch vehicle is designed to accommodate the maximum FPR loading.
Flight Performance Reserve Propellant Mass
FPR
An additional quantity of fuel to ensure depletion of high-weight oxidizer before fuel for systems with high-oxidizer mixing ratios (e.g., 6:1). This practice allows for more efficient propellant utilization.
Fuel Bias
http://en.wikipedia.org/wiki/Four_factor_formula
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(\varphi\)
"Fast Fission Factor" in an infinite medium, is the ratio of the mean number of neutrons produced by fission due to neutrons of all energies to the mean number of neutrons produced by fissions due to thermal neutrons only.
Fast Fission Factor
http://en.wikipedia.org/wiki/Heavy_fermion
http://www.iso.org/iso/catalogue_detail?csnumber=31897
k_F
Fermi Angular Wavenumber
http://en.wikipedia.org/wiki/Fermi_energy
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Fermi Energy" in a metal is the highest occupied energy level at zero thermodynamic temperature.
E_F
Fermi Energy
http://en.wikipedia.org/wiki/Fermi_energy
http://www.iso.org/iso/catalogue_detail?csnumber=31897
\(T_F = \frac{E_F}{k}\), where \(E_F\) is the Fermi energy and \(k\) is the Boltzmann constant.
"Fermi Temperature" is the temperature associated with the Fermi energy.
T_F
Fermi Temperature
M
Final Or Current Vehicle Mass
The first moment of area is the summation of area times distance to an axis. It is a measure of the distribution of the area of a shape in relationship to an axis.
First Moment of Area
Mass ratio for the first stage of a multistage launcher.
R_1
First Stage Mass Ratio
R/H
Fission Core Radius To Height Ratio
Fission Fuel Utilization Factor
The number of fission neutrons produced per absorption in the fuel.
Fission Multiplication Factor
\(\gamma\)
Flight path angle is defined in two different ways. To the aerodynamicist, it is the angle between the flight path vector (where the airplane is going) and the local atmosphere. To the flight crew, it is normally known as the angle between the flight path vector and the horizon, also known as the climb (or descent) angle.
Flight Path Angle
https://en.wikipedia.org/wiki/Flux
Flux describes any effect that appears to pass or travel (whether it actually moves or not) through a surface or substance. [Wikipedia]
Flux
"Force" is an influence that causes mass to accelerate. It may be experienced as a lift, a push, or a pull. Force is defined by Newton's Second Law as \(F = m \times a \), where \(F\) is force, \(m\) is mass and \(a\) is acceleration. Net force is mathematically equal to the time rate of change of the momentum of the body on which it acts. Since momentum is a vector quantity (has both a magnitude and direction), force also is a vector quantity.
\(L \cdot M/T^2\)
\(kg \cdot m/s^2\)
http://dbpedia.org/resource/Force
http://en.wikipedia.org/wiki/Force
http://www.iso.org/iso/catalogue_detail?csnumber=43012
\(F = \frac{dp}{dt}\), where \(F\) is the resultant force acting on a body, \(p\) is momentum of a body, and \(t\) is time.
F
http://en.wikipedia.org/wiki/Force
Force
http://wiki.answers.com/Q/What_is_magnitude_of_force
The 'magnitude' of a force is its 'size' or 'strength', regardless of the direction in which it acts.
U
Force Magnitude
\(M/L \cdot T^2\)
\(kg/m \cdot s^2\)
http://www.thefreedictionary.com/force+per+unit+area
true
The force applied to a unit area of surface; measured in pascals (SI unit) or in dynes (cgs unit)
p
http://en.wikipedia.org/wiki/Pressure
Force Per Area
\(M/L \cdot T^3\)
\(kg/m \cdot s^3\)
Force Per Area Time
The electric field depicts the force exerted on other electrically charged objects by the electrically charged particle the field is surrounding. The electric field is a vector field with SI units of newtons per coulomb (\(N C^{-1}\)) or, equivalently, volts per metre (\(V m^{-1}\) ). The SI base units of the electric field are \(kg m s^{-3} A^{-1}\). The strength or magnitude of the field at a given point is defined as the force that would be exerted on a positive test charge of 1 coulomb placed at that point
\(L \cdot M/I \cdot T^3\)
\(kg \cdot m/A \cdot s^3\)
http://en.wikipedia.org/wiki/Electric_field
Force per Electric Charge
\(M/T^2\)
\(kg/s^2\)
Force per Length
Fractional mass allocated to stage 1
A
Fractional Mass (Stage 1)
Fractional mass allocated to stage 2
B
Fractional Mass (Stage 2)
Fractional mass allocated to stage 3
C
Fractional Mass (Stage 3)
\(\gamma\)
Fraction of propellant and structural mass assigned to stages 1, 2 and 3.
Fractional Mass (Stages 1 through 3)
"Frequency" is the number of occurrences of a repeating event per unit time. The repetition of the events may be periodic (that is. the length of time between event repetitions is fixed) or aperiodic (i.e. the length of time between event repetitions varies). Therefore, we distinguish between periodic and aperiodic frequencies. In the SI system, periodic frequency is measured in hertz (Hz) or multiples of hertz, while aperiodic frequency is measured in becquerel (Bq). In spectroscopy, \(\nu\) is mostly used. Light passing through different media keeps its frequency, but not its wavelength or wavenumber.
\(/T\)
\(/s\)
http://dbpedia.org/resource/Frequency
\(f = 1/T\), where \(T\) is a period.
Alternatively,
\(\nu = 1/T\)
\(\nu, f\)
Frequency
http://dbpedia.org/resource/Friction
http://en.wikipedia.org/wiki/Friction
"Friction" is the force of two surfaces In contact, or the force of a medium acting on a moving object (that is air on an aircraft). When contacting surfaces move relative to each other, the friction between the two objects converts kinetic energy into thermal energy.
http://wiki.answers.com/Q/What_is_the_symbol_of_friction
Friction
http://dbpedia.org/resource/Friction
http://en.wikipedia.org/wiki/Friction
\(\mu\)
"Friction Coefficient" is the ratio of the force of friction between two bodies and the force pressing them together
http://wiki.answers.com/Q/What_is_the_symbol_of_friction
Friction Coefficient
http://en.wikipedia.org/wiki/Fugacity
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(\tilde{p}_B\)
"Fugacity" of a real gas is an effective pressure which replaces the true mechanical pressure in accurate chemical equilibrium calculations. It is equal to the pressure of an ideal gas which has the same chemical potential as the real gas.
Fugacity
http://www.matter.org.uk/diffraction/geometry/lattice_vectors.htm
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Fundamental Lattice vector" are fundamental translation vectors for the crystal lattice.
a_1, a_2, a_3
Fundamental Lattice vector
http://en.wikipedia.org/wiki/Reciprocal_lattice
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Fundamental Reciprocal Lattice Vector" are fundamental, or primary, translation vectors the reciprocal lattice.
b_1, b_2, b_3
Fundamental Reciprocal Lattice Vector
http://en.wikipedia.org/wiki/Landé_g-factor
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(g = \frac{\mu}{I\mu_B}\), where \(\mu\) is the magnitude of magnetic dipole moment, \(I\) is the nuclear angular momentum quantum number, and \(\mu_B\) is the Bohr magneton.
The "g-Factor of Nucleus" is associated with the spin and magnetic moments of protons, neutrons, and many nuclei.
g
g-Factor of Nucleus
The sum of a rocket's inert mass and usable fluids and gases at sea level.
http://en.wikipedia.org/wiki/Maximum_Takeoff_Weight
Gross Lift-Off Weight
http://dbpedia.org/resource/Gain
A general term used to denote an increase in signal power or signal strength in transmission from one point to another. Gain is usually expressed in decibels and is widely used to denote transducer gain. An increase or amplification. In radar there are two general usages of the term: (a) antenna gain, or gain factor, is the ratio of the power transmitted along the beam axis to that of an isotropic radiator transmitting the same total power; (b) receiver gain, or video gain, is the amplification given a signal by the receiver.
Gain
http://en.wikipedia.org/wiki/Band_gap
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Gap Energy" is the difference in energy between the lowest level of conduction band and the highest level of valence band. It is an energy range in a solid where no electron states can exist.
E_g
Gap Energy
http://en.wikipedia.org/wiki/Generalized_coordinates
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(q_i\), where \(q_i\) is one of the coordinates that is used to describe the position of the system under consideration, and \(N\) is the lowest number of coordinates necessary to fully define the position of the system.
Generalized Coordinates refers to the parameters that describe the configuration of the system relative to some reference configuration. These parameters must uniquely define the configuration of the system relative to the reference configuration.
q_i
Generalized Coordinate
http://en.wikipedia.org/wiki/Generalized_forces
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(\delta A = \sum Q_i\delta q_i\), where \(A\) is work and \(q_i\) is a generalized coordinate.
Generalized Forces find use in Lagrangian mechanics, where they play a role conjugate to generalized coordinates.
Q_i
Generalized Force
http://en.wikipedia.org/wiki/Momentum
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(p_i = \frac{\partial L}{\partial \dot{q_i}}\), where \(L\) is the Langrange function and \(\dot{q_i}\) is a generalized velocity.
Generalized Momentum, also known as the canonical or conjugate momentum, extends the concepts of both linear momentum and angular momentum. To distinguish it from generalized momentum, the product of mass and velocity is also referred to as mechanical, kinetic or kinematic momentum.
p_i
Generalized Force
http://en.wikipedia.org/wiki/Generalized_coordinates
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(\dot{q_i} = \frac{dq_i}{dt}\), where \(q_i\) is the generalized coordinate and \(t\) is time.
\(\dot{q_i}\)
Generalized Velocities are the time derivatives of the generalized coordinates of the system.
Generalized Velocity
http://en.citizendium.org/wiki/Thermodynamics
http://www.iso.org/iso/catalogue_detail?csnumber=31890
\(G = H - T \cdot S\), where \(H\) is enthalpy, \(T\) is thermodynamic temperature and \(S\) is entropy.
"Gibbs Energy} is one of the potentials are used to measure energy changes in systems as they evolve from an initial state to a final state. The potential used depends on the constraints of the system, such as constant temperature or pressure. \textit{Internal Energy} is the internal energy of the system, \textit{Enthalpy} is the internal energy of the system plus the energy related to pressure-volume work, and Helmholtz and Gibbs free energy are the energies available in a system to do useful work when the temperature and volume or the pressure and temperature are fixed, respectively. The name \textit{Gibbs Free Energy" is also used.
G
Gibbs Energy
http://en.wikipedia.org/wiki/Partition_function_(statistical_mechanics)
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(\Xi = \sum_{N_A, N_B, ...} Z(N_A, N_B, ...) \cdot \lambda_A^{N_A} \cdot \lambda_B^{N_B} \cdot ...\), where \(Z(N_A, N_B, ...)\) is the canonical partition function for the given number of particles \(A, B, ...,\), and \(\lambda_A, \lambda_B, ...\) are the absolute activities of particles \(A, B, ...\).
\(\Xi\)
An "Grand Canonical Partition Function" for a grand canonical ensemble, a system that can exchange both heat and particles with the environment, which has a constant temperature and a chemical potential.
Grand Canonical Partition Function
\(L^3/M \cdot T^2\)
\(m^3/kg \cdot s^2\)
http://www.thefreedictionary.com/gravitational+attraction
The force of attraction between all masses in the universe; especially the attraction of the earth's mass for bodies near its surface; the more remote the body the less the gravity; the gravitation between two bodies is proportional to the product of their masses and inversely proportional to the square of the distance between them.
G
Gravitational Attraction
\(qkdv:A0E0L0I0M0H0T0D1\)
https://en.wikipedia.org/wiki/API_gravity
http://www.iso.org/iso/catalogue_detail?csnumber=31894
The American Petroleum Institute gravity, or API gravity, is a measure of how heavy or light a petroleum liquid is compared to water: if its API gravity is greater than 10, it is lighter and floats on water; if less than 10, it is heavier and sinks.
API gravity is thus an inverse measure of a petroleum liquid's density relative to that of water (also known as specific gravity). It is used to compare densities of petroleum liquids. For example, if one petroleum liquid is less dense than another, it has a greater API gravity. Although API gravity is mathematically a dimensionless quantity (see the formula below), it is referred to as being in 'degrees'. API gravity is graduated in degrees on a hydrometer instrument. API gravity values of most petroleum liquids fall between 10 and 70 degrees.
API Gravity
http://en.wikipedia.org/wiki/Speed_of_sound
\(c_g = \frac{d\omega}{dk}\), where \(\omega\) is the angular frequency and \(k\) is angular wavenumber.
In a dispersive medium sound speed is a function of sound frequency, through the dispersion relation. The spatial and temporal distribution of a propagating disturbance will continually change. The group speed of sound describes the propagation of the disturbance.
c
belongs to SOQ-ISO
Group Speed of Sound
http://en.wikipedia.org/wiki/Grüneisen_parameter
http://www.iso.org/iso/catalogue_detail?csnumber=31897
\(\gamma = \frac{\alpha_V}{x_T c_V\rho}\), where \(\alpha_V\) is the cubic expansion coefficient, \(x_T\) is isothermal compressibility, \(c_V\) is specific heat capacity at constant volume, and \(\rho\) is mass density.
\(\gamma\)
"Gruneisen Parameter" named after Eduard Grüneisen, describes the effect that changing the volume of a crystal lattice has on its vibrational properties, and, as a consequence, the effect that changing temperature has on the size or dynamics of the lattice.
Gruneisen Parameter
http://www.iso.org/iso/catalogue_detail?csnumber=43012
\(\overline{T_g}\)
"Gustatory Threshold" are thresholds for classes of tast that can be detected by the human mouth and thresholds of sensitivity to foods, drinks and other substances.
Gustatory Threshold
"Gyromagnetic Ratio}, also sometimes known as the magnetogyric ratio in other disciplines, of a particle or system is the ratio of its magnetic dipole moment to its angular momentum, and it is often denoted by the symbol, \(\gamma\). Its SI units are radian per second per tesla (\(rad s^{-1} \cdot T^{1}\)) or, equivalently, coulomb per kilogram (\(C \cdot kg^{-1"\)).
http://dbpedia.org/resource/Gyromagnetic_ratio
http://en.wikipedia.org/wiki/Gyromagnetic_ratio
\(\mu = \gamma J\), where \(\mu\) is the magnetic dipole moment, and \(J\) is the total angular momentum.
\(\gamma\)
Gyromagnetic Ratio
http://en.wikipedia.org/wiki/Half-life
http://www.iso.org/iso/catalogue_detail?csnumber=31895
The "Half-Life" is the average duration required for the decay of one half of the atoms or nuclei.
T_{1/2}
Half-life
http://en.wikipedia.org/wiki/Half-value_layer
http://www.iso.org/iso/catalogue_detail?csnumber=31895
The "Half-Value Thickness" is the thickness of the material at which the intensity of radiation entering it is reduced by one half.
d_{1/2}
Half-Value Thickness
http://en.wikipedia.org/wiki/Hall_effect
http://www.iso.org/iso/catalogue_detail?csnumber=31897
In an isotropic conductor, the relation between electric field strength, \(E\), and electric current density, \(J\) is \(E = \rho J + R_H(B X J)\), where \(\rho\) is resistivity, and \(B\) is magnetic flux density.
"Hall Coefficient" is defined as the ratio of the induced electric field to the product of the current density and the applied magnetic field.
R_H, A_H
Hall Coefficient
http://en.wikipedia.org/wiki/Hamilton–Jacobi_equation
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(H = \sum p_i\dot{q_i} - L\), where \(p_i\) is a generalized momentum, \(\dot{q_i}\) is a generalized velocity, and \(L\) is the Lagrange function.
The Hamilton–Jacobi equation (HJE) is a necessary condition describing extremal geometry in generalizations of problems from the calculus of variations.
H
Hamilton Function
HEP
Head End Pressure
http://dbpedia.org/resource/Heart_rate
http://www.medterms.com/script/main/art.asp?articlekey=3674
http://www.oxfordreference.com/view/10.1093/oi/authority.20110803100354463
The number of heartbeats per unit of time, usually per minute. The heart rate is based on the number of contractions of the ventricles (the lower chambers of the heart). The heart rate may be too fast (tachycardia) or too slow (bradycardia). The average adult pulse rate at rest is 60–80 per minute, but exercise, injury, illness, and emotion may produce much faster rates.
Heart Rate
heat
http://dbpedia.org/resource/Heat
http://www.iso.org/iso/catalogue_detail?csnumber=31890
"Heat" is the energy transferred by a thermal process. Heat can be measured in terms of the dynamical units of energy, as the erg, joule, etc., or in terms of the amount of energy required to produce a definite thermal change in some substance, as, for example, the energy required per degree to raise the temperature of a unit mass of water at some temperature ( calorie, Btu).
Q
Heat
"Heat Capacity" (usually denoted by a capital \(C\), often with subscripts), or thermal capacity, is the measurable physical quantity that characterizes the amount of heat required to change a substance's temperature by a given amount. In the International System of Units (SI), heat capacity is expressed in units of joule(s) (J) per kelvin (K).
http://en.wikipedia.org/wiki/Heat_capacity
\(C = dQ/dT\), where \(Q\) is amount of heat and \(T\) is thermodynamic temperature.
C_P
Heat Capacity
The heat capacity ratio, or ratio of specific heats, is the ratio of the heat capacity at constant pressure (\(C_P\)) to heat capacity at constant volume (\(C_V\)). For an ideal gas, the heat capacity is constant with temperature (\(\theta\)). Accordingly we can express the enthalpy as \(H = C_P*\theta\) and the internal energy as \(U = C_V \cdot \theta\). Thus, it can also be said that the heat capacity ratio is the ratio between enthalpy and internal energy.
http://dbpedia.org/resource/Heat_capacity_ratio
http://en.wikipedia.org/wiki/Heat_capacity_ratio
http://www.iso.org/iso/catalogue_detail?csnumber=31890
Heat Capacity Ratio
The rate of heat flow between two systems is measured in watts (joules per second). The formula for rate of heat flow is \(\bigtriangleup Q / \bigtriangleup t = -K \times A \times \bigtriangleup T/x\), where \(\bigtriangleup Q / \bigtriangleup t\) is the rate of heat flow; \(-K\) is the thermal conductivity factor; A is the surface area; \(\bigtriangleup T\) is the change in temperature and \(x\) is the thickness of the material. \(\bigtriangleup T/ x\) is called the temperature gradient and is always negative because of the heat of flow always goes from more thermal energy to less).
\(heat-flow-rate\)
http://en.wikipedia.org/wiki/Rate_of_heat_flow
\(\Phi\)
Heat Flow Rate
\(\textit{Heat Flux}\) is the heat rate per unit area. In SI units, heat flux is measured in \(W/m^2\). Heat rate is a scalar quantity, while heat flux is a vectorial quantity. To define the heat flux at a certain point in space, one takes the limiting case where the size of the surface becomes infinitesimally small.
http://en.wikipedia.org/wiki/Heat_flux
http://www.iso.org/iso/catalogue_detail?csnumber=31890
Heat Flow Rate per Unit Area
Heat Flux Density
height
http://dbpedia.org/resource/Height
http://en.wikipedia.org/wiki/Height
http://www.iso.org/iso/catalogue_detail?csnumber=43012
"Height" is the measurement of vertical distance, but has two meanings in common use. It can either indicate how "tall" something is, or how "high up" it is.
h
Height
\(\textit{Helmholtz Energy}\) is one of the potentials are used to measure energy changes in systems as they evolve from an initial state to a final state. The potential used depends on the constraints of the system, such as constant temperature or pressure. \(\textit{Internal Energy}\) is the internal energy of the system, \(\textit{Enthalpy}\) is the internal energy of the system plus the energy related to pressure-volume work, and Helmholtz and Gibbs free energy are the energies available in a system to do useful work when the temperature and volume or the pressure and temperature are fixed, respectively. The name \(\textit{Helmholz Free Energy}\) is also used.
http://en.citizendium.org/wiki/Thermodynamics
http://www.iso.org/iso/catalogue_detail?csnumber=31890
\(H = U - T \cdot S\), where \(U\) is internal energy, \(T\) is thermodynamic temperature and \(S\) is entropy.
A
Helmholtz Energy
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Hole Density" is the number of holes per volume in a valence band.
p
Hole Density
Component of a projectile's velocity, which acts parallel to the ground and does not lift the projectile in the air.
V_{X}
Horizontal Velocity
http://en.wikipedia.org/wiki/Hyperfine_structure
http://en.wikipedia.org/wiki/Quantum_number
http://www.iso.org/iso/catalogue_detail?csnumber=31894
The "Hyperfine Structure Quantum Number" is a quantum number of an atom describing inclination of the nuclear spin with respect to a quantization axis given by the magnetic field produced by the orbital electrons.
F
Hyperfine Structure Quantum Number
The sum of the vehicle dry mass, residual fluids and gasses, personnel and personnel provisions, and cargo.
Inert Mass
Ignition interval time
http://dbpedia.org/resource/Illuminance
\(E_v = \frac{d\Phi}{dA}\), where \(d\Phi\) is the luminous flux incident on an element of the surface with area \(dA\).
Illuminance is the total luminous flux incident on a surface, per unit area. It is a measure of the intensity of the incident light, wavelength-weighted by the luminosity function to correlate with human brightness perception.
Illuminance
http://dbpedia.org/resource/Electrical_impedance
http://en.wikipedia.org/wiki/Electrical_impedance
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=131-12-43
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
http://www.iso.org/iso/catalogue_detail?csnumber=43012
\(\underline{Z} = \underline{U} / \underline{I}\), where \(\underline{U}\) is the voltage phasor and \(\underline{I}\) is the electric current phasor.
\(\underline{Z}\)
"Impedance" is the measure of the opposition that a circuit presents to the passage of a current when a voltage is applied. In quantitative terms, it is the complex ratio of the voltage to the current in an alternating current (AC) circuit. Impedance extends the concept of resistance to AC circuits, and possesses both magnitude and phase, unlike resistance, which has only magnitude. When a circuit is driven with direct current (DC), there is no distinction between impedance and resistance; the latter can be thought of as impedance with zero phase angle.
Impedance
https://en.wikipedia.org/wiki/Incidence_(epidemiology)
In epidemiology, incidence is a measure of the probability of occurrence of a given medical condition in a population within a specified period of time.
Incidence
https://en.wikipedia.org/wiki/Cumulative_incidence
https://en.wikipedia.org/wiki/Incidence_(epidemiology)
Incidence proportion (also known as cumulative incidence) is the number of new cases within a specified time period divided by the size of the population initially at risk. For example, if a population initially contains 1,000 non-diseased persons and 28 develop a condition over two years of observation, the incidence proportion is 28 cases per 1,000 persons per two years, i.e. 2.8% per two years.
Incidence Proportion
https://en.wikipedia.org/wiki/Incidence_(epidemiology)
The incidence rate is a measure of the frequency with which a disease or other incident occurs over a specified time period. It is also known as the incidence density rate or person-time incidence rate, when the denominator is the combined person-time of the population at risk (the sum of the time duration of exposure across all persons exposed)
Incidence Rate
\(L^2 \cdot M/I^2 \cdot T^2\)
\(kg \cdot m^2/A^2 \cdot s^2\)
http://dbpedia.org/resource/Inductance
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=131-12-19
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(L =\frac{\Psi}{I}\), where \(I\) is an electric current in a thin conducting loop, and \(\Psi\) is the linked flux caused by that electric current.
"Inductance" is an electromagentic quantity that characterizes a circuit's resistance to any change of electric current; a change in the electric current through induces an opposing electromotive force (EMF). Quantitatively, inductance is proportional to the magnetic flux per unit of electric current.
L
Inductance
http://en.wikipedia.org/wiki/Four_factor_formula
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(k_\infty\)
The "Infinite Multiplication Factor" is the multiplication factor for an infinite medium or for an infinite repeating lattice.
Infinite Multiplication Factor
http://simple.wikipedia.org/wiki/Information_entropy
Information Entropy is a concept from information theory. It tells how much information there is in an event. In general, the more uncertain or random the event is, the more information it will contain. The concept of information entropy was created by a mathematician. He was named Claude Elwood Shannon. It has applications in many areas, including lossless data compression, statistical inference, cryptography and recently in other disciplines as biology, physics or machine learning.
Information Entropy
Information flow rate
Initial Expansion Ratio
Initial Nozzle Throat Diameter
M_{o}
Initial Vehicle Mass
The velocity of a moving body at starting; especially, the velocity of a projectile as it leaves the mouth of a firearm from which it is discharged.
V_{i}
Initial Velocity
"Instantaneous Power}, for a two-terminal element or a two-terminal circuit with terminals A and B, is the product of the voltage \(u_{AB}\) between the terminals and the electric current i in the element or circuit: \(p = \)u_{AB} \cdot i\(, where \)u_{AB" is the line integral of the electric field strength from A to B, and where the electric current in the element or circuit is taken positive if its direction is from A to B and negative in the opposite case. For an n-terminal circuit, it is the sum of the instantaneous powers relative to the n - 1 pairs of terminals when one of the terminals is chosen as a common terminal for the pairs. For a polyphase element, it is the sum of the instantaneous powers in all phase elements of a polyphase element. For a polyphase line consisting of m line conductors and one neutral conductor, it is the sum of the m instantaneous powers expressed for each line conductor by the product of the polyphase line-to-neutral voltage and the corresponding line current.
http://en.wikipedia.org/wiki/Power
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=131-11-30
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=131-11-31
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=141-02-14
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=141-03-10
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(p = ui\), where \(u\) is instantaneous voltage and \(i\) is instantaneous electric current.
p
Instantaneous Power
http://en.wikipedia.org/wiki/Internal_conversion_coefficient
http://www.iso.org/iso/catalogue_detail?csnumber=31895
The "InternalConversionFactor" describes the rate of internal conversion. It is the ratio of the number of internal conversion electrons to the number of gamma quanta emitted by the radioactive atom in a given transition.
a
InternalConversionFactor
int-energy
http://dbpedia.org/resource/Internal_energy
http://en.citizendium.org/wiki/Internal_energy
For a closed thermodynamic system, \(\Delta U = Q + W\), where \(Q\) is amount of heat transferred to the system and \(W\) is work done on the system provided that no chemical reactions occur.
http://www.iso.org/iso/catalogue_detail?csnumber=31890
"Internal Energy" is simply its energy. "internal" refers to the fact that some energy contributions are not considered. For instance, when the total system is in uniform motion, it has kinetic energy. This overall kinetic energy is never seen as part of the internal energy; one could call it external energy. Or, if the system is at constant non-zero height above the surface the Earth, it has constant potential energy in the gravitational field of the Earth. Gravitational energy is only taken into account when it plays a role in the phenomenon of interest, for instance in a colloidal suspension, where the gravitation influences the up- downward motion of the small particles comprising the colloid. In all other cases, gravitational energy is assumed not to contribute to the internal energy; one may call it again external energy.
U
Internal Energy
\(np = n_i^2\), where \(n\) is electron density and \(p\) is hole density.
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Intinsic Carrier Density" is proportional to electron and hole densities.
n_i
Intinsic Carrier Density
\(/M\)
\(/mol\)
Inverse amount of substance
\(T^2/L^2 \cdot M\)
\(s^2/kg \cdot m^2\)
Inverse Energy
Reciprocal length or inverse length is a measurement used in several branches of science and mathematics. As the reciprocal of length, common units used for this measurement include the reciprocal metre or inverse metre (\(m^{-1}\)), the reciprocal centimetre or inverse centimetre (\(cm^{-1}\)), and, in optics, the dioptre.
\(/L\)
\(/m\)
http://en.wikipedia.org/wiki/Reciprocal_length
Inverse Length
\(/K \cdot m\)
\(/\Theta \cdot L\)
Inverse Length Temperature
\(A \cdot s^2/kg \cdot m^2\)
\(I \cdot T^2/L^2 \cdot M\)
Inverse Magnetic Flux
\(L^3 \cdot M/I^2 \cdot T^4\)
\(kg \cdot m^3/A^2 \cdot s^4\)
Inverse Permittivity
Inverse Pressure
\(T^4/L^4 \cdot M^2\)
\(s^4/kg^2 \cdot m^4\)
Inverse Square Energy
Inverse Square Mass
\(/T^2\)
Inverse Square Time
Inverse Temperature
\(/T\)
Inverse Time
\(/K \cdot s\)
\(/\Theta \cdot T\)
Inverse Time Temperature
\(/m^3\)
Inverse Volume
An ion current is the influx and/or efflux of ions through an ion channel.
j
Ion Current
http://www.answers.com/topic/ion-density
\(n^+ = \frac{N^+}{V}\), \(n^- = \frac{N^-}{V}\)
where \(N^+\) and \(N^-\) are the number of positive and negative ions, respectively, in a 3D domain with volume \(V\).
http://www.iso.org/iso/catalogue_detail?csnumber=31895
"Ion Density" is the number of ions per unit volume. Also known as ion concentration.
N, n^+, n^-
Ion Density
http://en.wikipedia.org/wiki/Ion_transport_number
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(t_B = \frac{i_B}{i}\), where \(i_B\) is the electric current carried by the ion \(B\) and \(i\) is the total electric current.
The "Ion Transport Number" is a quantity which indicates the different contribution of ions to the electric current in electrolytes due to different electrical mobility.
t_B
Ion Transport Number
The total charge of an ion. The charge of an electron; the charge of any ion is equal to this electron charge in magnitude, or is an integral multiple of it.
q
Ionic Charge
http://en.wikipedia.org/wiki/Ionic_strength
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(I = \frac{1}{2} \sum z_i^2 b_i\), where the summation is carried out over all ions with charge number \(z_i\) and molality \(m_i\).
The "Ionic Strength" of a solution is a measure of the concentration of ions in that solution.
I
Ionic Strength
http://en.wikipedia.org/wiki/Ionization_energy
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Ionization Energy" is the energy difference between an electron at rest at infinity and an electron at a certain energy level. The amount of energy required to remove an electron from that atom or molecule in the gas phase.
E_i
Ionization Energy
W-PER-M2
\(E = \frac{d\Phi}{dA}\), where \(d\Phi\) is the radiant flux incident on an element of the surface with area \(dA\).
Irradiance and Radiant Emittance are radiometry terms for the power per unit area of electromagnetic radiation at a surface. "Irradiance" is used when the electromagnetic radiation is incident on the surface. "Radiant emmitance" (or "radiant exitance") is used when the radiation is emerging from the surface.
E
Irradiance
http://en.wikipedia.org/wiki/Compressibility
http://www.iso.org/iso/catalogue_detail?csnumber=31890
\(\varkappa_S = \frac{1}{V}\left (\frac{\partial V}{\partial p} \right )_S\), where \(V\) is volume, \(p\) is \(pressure\), and \(S\) is entropy,
\(\varkappa_S\)
Isentropic compressibility is the extent to which a material reduces its volume when it is subjected to compressive stresses at a constant value of entropy.
Isentropic Compressibility
Isentropic exponent is a variant of "Specific Heat Ratio Capacities}. For an ideal gas \textit{Isentropic Exponent"\(, \varkappa\). is equal to \(\gamma\), the ratio of its specific heat capacities \(c_p\) and \(c_v\) under steady pressure and volume.
http://en.citizendium.org/wiki/Specific_heat_ratio
http://en.wikipedia.org/wiki/Compressibility
http://www.iso.org/iso/catalogue_detail?csnumber=31890
\(\varkappa = -\frac{V}{p}\left \{ \frac{\partial p}{\partial V}\right \}_S\), where \(V\) is volume, \(p\) is pressure, and \(S\) is entropy.
\(\varkappa\)
Isentropic Exponent
http://en.wikipedia.org/wiki/Compressibility
\(\varkappa_T = \frac{1}{V}\left (\frac{\partial V}{\partial p} \right )_T\), where \(V\) is volume, \(p\) is \(pressure\), and \(T\) is thermodynamic temperature.
\(\varkappa_T\)
The isothermal compressibility defines the rate of change of system volume with pressure.
Isothermal compressibility
http://en.wikipedia.org/wiki/Kerma_(physics)
http://www.iso.org/iso/catalogue_detail?csnumber=31895
For indirectly ionizing (uncharged) particles, \(K= \frac{dE_{tr}}{dm}\), where \(dE_{tr}\) is the mean sum of the initial kinetic energies of all the charged ionizing particles liberated by uncharged ionizing particles in an element of matter, and \(dm\) is the mass of that element.
"Kerma" is the sum of the initial kinetic energies of all the charged particles liberated by uncharged ionizing radiation (i.e., indirectly ionizing radiation such as photons and neutrons) in a sample of matter, divided by the mass of the sample.
K
Kerma
http://en.wikipedia.org/wiki/Half-value_layer
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(\dot{K} = \frac{dK}{dt}\), where \(K\) is the increment of kerma during time interval with duration \(t\).
\(\dot{K}\)
"Kerma Rate" is the kerma per unit time.
Kerma Rate
The ratio of the viscosity of a liquid to its density. Viscosity is a measure of the resistance of a fluid which is being deformed by either shear stress or tensile stress. In many situations, we are concerned with the ratio of the inertial force to the viscous force (that is the Reynolds number), the former characterized by the fluid density \(\rho\). This ratio is characterized by the kinematic viscosity (Greek letter \(\nu\)), defined as follows: \(\nu = \mu / \rho\). The SI unit of \(\nu\) is \(m^{2}/s\). The SI unit of \(\nu\) is \(kg/m^{1}\).
http://dbpedia.org/resource/Viscosity
http://en.wikipedia.org/wiki/Viscosity
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(\nu = \frac{\eta}{\rho}\), where \(\eta\) is dynamic viscosity and \(\rho\) is mass density.
\(\nu\)
Kinematic Viscosity
\(\textit{Kinetic Energy}\) is the energy which a body possesses as a consequence of its motion, defined as one-half the product of its mass \(m\) and the square of its speed \(v\), \( \frac{1}{2} mv^{2} \). The kinetic energy per unit volume of a fluid parcel is the \( \frac{1}{2} p v^{2}\) , where \(p\) is the density and \(v\) the speed of the parcel. See potential energy. For relativistic speeds the kinetic energy is given by \(E_k = mc^2 - m_0 c^2\), where \(c\) is the velocity of light in a vacuum, \(m_0\) is the rest mass, and \(m\) is the moving mass.
http://dbpedia.org/resource/Kinetic_energy
http://en.wikipedia.org/wiki/Kinetic_energy
\(T = \frac{mv^2}{2}\), where \(m\) is mass and \(v\) is speed.
http://www.iso.org/iso/catalogue_detail?csnumber=31889
K
KE
http://en.wikipedia.org/wiki/Kinetic_energy
Kinetic Energy
http://en.wikipedia.org/wiki/Lagrangian
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=113-03-76
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(L(q_i, \dot{q_i}) = T(q_i, \dot{q_i}) - V(q_i)\), where \(T\) is kinetic energy, \(V\) is potential energy, \(q_i\) is a generalized coordinate, and \(\dot{q_i}\) is a generalized velocity.
The Lagrange Function is a function that summarizes the dynamics of the system.
L
Lagrange Function
http://en.wikipedia.org/wiki/Ginzburg–Landau_theory
http://www.iso.org/iso/catalogue_detail?csnumber=31897
At zero thermodynamic temperature \(\kappa = \frac{\lambda_L}{(\varepsilon\sqrt{2})}\), where \(\lambda_L\) is London penetration depth and \(\varepsilon\) is coherence length.
\(\kappa\)
"Landau-Ginzburg Number", also known as the Ginzburg-Landau parameter, describes the relationship between London penetration depth and coherence length.
Landau-Ginzburg Number
http://en.wikipedia.org/wiki/G-factor_(physics)
http://en.wikipedia.org/wiki/Landé_g-factor
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(g = \frac{\mu}{J\mu_B}\), where \(\mu\) is the magnitude of magnetic dipole moment, \(J\) is the total angular momentum quantum number, and \(\mu_B\) is the Bohr magneton.
The "Lande g-Factor" is a particular example of a g-factor, namely for an electron with both spin and orbital angular momenta. It is named after Alfred Landé, who first described it in 1921.
g
Lande g-Factor
http://en.wikipedia.org/wiki/Larmor_precession#Larmor_frequency
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(\omega_L = \frac{e}{2m_e}B\), where \(e\) is the elementary charge, \(m_e\) is the rest mass of electron, and \(B\) is the magnetic flux density.
\(\omega_L\)
The "Larmor Frequency" describes angular momentum vector precession about the external field axis with an angular frequency.
Larmor Angular Frequency
http://www.matter.org.uk/diffraction/geometry/lattice_vectors.htm
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Lattice Plane Spacing" is the distance between successive lattice planes.
d
Lattice Plane Spacing
http://www.matter.org.uk/diffraction/geometry/lattice_vectors.htm
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Lattice Vector" is a translation vector that maps the crystal lattice on itself.
R
Lattice Vector
\(leakage-factor\)
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=221-04-12
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(\sigma = 1 - k^2\), where \(k\) is the coupling factor.
\(\sigma\)
"Leakage Factor" is the ratio of the total magnetic flux to the useful magnetic flux of a magnetic circuit.
Leakage Factor
\(L\)
\(m\)
http://dbpedia.org/resource/Length
http://en.wikipedia.org/wiki/Length
In geometric measurements, length most commonly refers to the est dimension of an object. In some contexts, the term "length" is reserved for a certain dimension of an object along which the length is measured.
l
Length
Length Force
\(L^3 \cdot M/T^2\)
\(kg \cdot m^3/s^2\)
Length Energy
\(L \cdot M\)
\(kg \cdot m\)
Length Mass
\(L^3 \cdot M/M \cdot T^2\)
\(kg \cdot m^3/mol \cdot s^2\)
Length Molar Energy
\(L/I\)
\(m/A\)
Length per Unit Electric Current
Length Percentage
\(K \cdot m\)
\(\Theta \cdot L\)
Length Temperature
Length Temperature Time
http://www.scribd.com/doc/51548050/149/Lethargy
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(u = \ln(\frac{E_0}{E})\), where \(E_0\) is a reference energy.
The "Lethargy" is a dimensionless logarithm of the ratio of the energy of source neutrons to the energy of neutrons after a collision.
u
Lethargy
http://encyclopedia2.thefreedictionary.com/Level+Width
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(\Gamma = \frac{\hbar}{\tau}\), where \(\hbar\) is the reduced Planck constant and \(\tau\) is the mean lifetime.
\(\Gamma\)
The "Level Width" is the uncertainty in the energy of a quantum-mechanical system having discrete energy levels in a state that is not strictly stationary. The system may be an atom, a molecule, or an atomic nucleus.
Level Width
The lift coefficient is a dimensionless coefficient that relates the lift generated by a lifting body, the dynamic pressure of the fluid flow around the body, and a reference area associated with the body.
C_{L}
Lift Coefficient
The lift force, lifting force or simply lift is the sum of all the forces on a body that force it to move perpendicular to the direction of flow.
L
Lift Force
\(\alpha(\lambda) = \frac{1}{\Phi_\lambda(\lambda)}\frac{d\Phi_\lambda(\lambda)}{dl}\), where \(\frac{d\Phi}{\Phi}\) is the relative decrease, caused by absorption, in the spectral radiant flux \(\Phi\) of a collimated beam of electromagnetic radiation corresponding to the wavelength \(\lambda\) during traversal of an infinitesimal layer of a medium and \(dl\) is the length traversed.
\(\mu\)
The Linear Absorption Coefficient is a quantity that characterizes how easily a material or medium can be penetrated by a beam of light, sound, particles, or other energy or matter.
Linear Absorption Coefficient
\(L/T^2\)
\(m/s^2\)
http://dbpedia.org/resource/Acceleration
Linear Acceleration
http://en.wikipedia.org/wiki/Attenuation_coefficient
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(\mu = -\frac{1}{J}\frac{dJ}{dx}\), where \(J\) is the magnitude of the current rate of a beam of particles parallel to the \(x-direction\).
Or:
\(\mu(\lambda) = \frac{1}{\Phi_\lambda(\lambda)}\frac{d\Phi_\lambda(\lambda)}{dl}\), where \(\frac{d\Phi}{\Phi}\) is the relative decrease in the spectral radiant flux \(\Phi\) of a collimated beam of electromagnetic radiation corresponding to the wavelength \(\lambda\) during traversal of an infinitesimal layer of a medium and \(dl\) is the length traversed.
\(\mu\)
"Linear Attenuation Coefficient", also called the attenuation coefficient, narrow beam attenuation coefficient, or absorption coefficient, is a quantity that characterizes how easily a material or medium can be penetrated by a beam of light, sound, particles, or other energy or matter.
Linear Attenuation Coefficient
\(kg m^{-1}\)
http://en.wikipedia.org/wiki/Linear_density
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(\rho_l = \frac{dm}{dl}\), where \(m\) is mass and \(l\) is length.
\(\rho_l\)
The Linear density, linear mass density or linear mass is a measure of mass per unit of length, and it is a characteristic of strings or other one-dimensional objects.
Linear Density
\(A/m\)
http://www.asknumbers.com/ElectricalConversion.aspx
"Linear Electric Linear Current" is the electric current per unit line.
Linear Electric Current
"Linear Electric Linear Current Density" is the electric current per unit length. Electric current, \(I\), through a curve \(C\) is defined as \(I = \int_C J _s \times e_n\), where \(e_n\) is a unit vector perpendicular to the surface and line vector element, and \(dr\) is the differential of position vector \(r\).
http://www.asknumbers.com/ElectricalConversion.aspx
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(J_s = \rho_A v\), where \(\rho_A\) is surface density of electric charge and \(v\) is velocity.
J_s
Linear Electric Current Density
http://dbpedia.org/resource/Linear_energy_transfer
http://en.wikipedia.org/wiki/Linear_energy_transfer
http://www.iso.org/iso/catalogue_detail?csnumber=31895
For ionizing charged particles, \(L_\Delta = \frac{dE_\Delta}{dl}\), where \(dE_\Delta\) is the mean energy lost in elctronic collisions locally to matter along a small path through the matter, minus the sum of the kinetic energies of all the electrons released with kinetic energies in excess of \(\Delta\), and \(dl\) is the length of that path.
\(L_\Delta\)
\(L_\bigtriangleup\)
"Linear Energy Transfer" (LET) is the linear density of energy lost by a charged ionizing particle travelling through matter.Typically, this measure is used to quantify the effects of ionizing radiation on biological specimens or electronic devices.
Linear Energy Transfer
\(lnr-exp-coef\)
http://www.iso.org/iso/catalogue_detail?csnumber=31890
\(\alpha_l = \frac{1}{l} \; \frac{dl}{dT}\), where \(l\) is \(length\) and \(T\) is thermodynamic temperature.
\(\alpha_l\)
Linear Expansion Coefficient
http://en.wikipedia.org/wiki/Ionization#Classical_ionization
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(N_{il} = \frac{1}{e}\frac{dQ}{dl}\), where \(e\) is the elementary charge and \(dQ\) is the average total charge of all positive ions produced over an infinitesimal element of the path with length \(dl\) by an ionizing charged particle.
"Linear Ionization" is a description of how the ionization of an atom or molecule takes place. For example, an ion with a +2 charge can be created only from an ion with a +1 charge or a +3 charge. That is, the numerical charge of an atom or molecule must change sequentially, always moving from one number to an adjacent, or sequential, number. Using sequential ionization definition.
N_{il}
Linear Ionization
Linear momentum is the quantity obtained by multiplying the mass of a body by its linear velocity. The momentum of a continuous medium is given by the integral of the velocity over the mass of the medium or by the product of the total mass of the medium and the velocity of the center of gravity of the medium.The SI unit for linear momentum is meter-kilogram per second (\(m-kg/s\)).
\(L \cdot M/T\)
\(kg \cdot m/s\)
http://dbpedia.org/resource/Momentum
p = m\upsilon
p
http://en.wikipedia.org/wiki/Momentum
Linear Momentum
http://en.wikipedia.org/wiki/Deformation_(mechanics)
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(\xi = \frac{\Delta l}{l_0}\), where \(\Delta l\) is the increase in length and \(l_0\) is the length in a reference state to be specified.
\(\xi\)
A strain is a normalized measure of deformation representing the displacement between particles in the body relative to a reference length.
Linear Strain
\(L/\Theta\)
\(m/K\)
http://en.wikipedia.org/linear_thermal_expansion
When the temperature of a substance changes, the energy that is stored in the intermolecular bonds between atoms changes. When the stored energy increases, so does the length of the molecular bonds. As a result, solids typically expand in response to heating and contract on cooling; this dimensional response to temperature change is expressed by its coefficient of thermal expansion. Different coefficients of thermal expansion can be defined for a substance depending on whether the expansion is measured by: linear thermal expansion, area thermal expansion, or volumetric thermal expansion.
Linear Thermal Expansion
Linear Velocity, as the name implies deals with speed in a straight line, the units are often \(km/hr\) or \(m/s\) or \(mph\) (miles per hour). Linear Velocity (v) = change in distance/change in time, where \(v = \bigtriangleup d/\bigtriangleup t\)
\(L/T\)
\(m/s\)
http://dbpedia.org/resource/Velocity
http://au.answers.yahoo.com/question/index?qid=20080319082534AAtrClv
v
Linear Velocity
"Linked Flux" is defined as the path integral of the magnetic vector potential. This is the line integral of a magnetic vector potential \(A\) along a curve \(C\). The line vector element \(dr\) is the differential of position vector \(r\).
http://dbpedia.org/resource/Magnetic_flux
\(linked-flux\)
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=121-11-24
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
http://www.oxfordreference.com/view/10.1093/acref/9780199233991.001.0001/acref-9780199233991-e-1800
\(\Psi_m = \int_C A \cdot dr\), where \(A\) is magnetic vector potential and \(dr\) is the vector element of the curve \(C\).
\(\Psi\)
\(\Psi_m\)
Linked Flux
http://www.ehow.com/facts_6371078_liquid-volume_.html
Liquid volume is the volume of a given amount of liquid, that is, the amount of space a liquid takes up. There are a number of different units used to measure liquid volume, but most of them fall under either the metric system of measurement or the Imperial system of measurement.
Liquid Volume
\(G = \log_{2}(f2/f1)\), where \(f1\) and \(f2 \geq f1\) are frequencies of two tones.
belongs to SOQ-ISO
Logarithmic frequency interval
http://en.wikipedia.org/wiki/London_penetration_depth
If an applied magnetic field is parallel to the plane surface of a semi-infinite superconductor, the field penetrates the superconductor according to the expression \(B(x) = B(0) \exp{(\frac{-x}{\lambda_L})}\), where \(B\) is magnetic flux density and \(x\) is the distance from the surface.
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"London Penetration Depth" characterizes the distance to which a magnetic field penetrates into a superconductor and becomes equal to 1/e times that of the magnetic field at the surface of the superconductor.
λₗ
London Penetration Depth
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Long-Range Order Parameter" is the fraction of atoms in an Ising ferromagnet having magnetic moments in one direction, minus the fraction having magnetic moments in the opposite direction.
R, s
Long-Range Order Parameter
http://www.matter.org.uk/diffraction/geometry/lattice_vectors.htm
http://www.iso.org/iso/catalogue_detail?csnumber=31897
\(L = \frac{\lambda}{\sigma T}\), where \(\lambda\) is thermal conductivity, \(\sigma\) is electric conductivity, and \(T\) is thermodynamic temperature.
"Lorenz Coefficient" is part mof the Lorenz curve.
L
Lorenz Coefficient
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(\delta = \arctan d\), where \(d\) is loss factor.
\(\delta\)
Loss Angle
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(d = \frac{1}{Q}\), where \(Q\) is quality factor.
"Loss Factor} is the inverse of \textit{Quality Factor} and is the ratio of the \textit{resistance} and modulus of \textit{reactance".
d
Loss Factor
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Lower Critical Magnetic Flux Density" for type II superconductors, is the threshold magnetic flux density for magnetic flux entering the superconductor.
B_{c1}
Lower Critical Magnetic Flux Density
\(J/L^2\)
\(cd/m^2\)
http://dbpedia.org/resource/Luminance
\(L_v = \frac{dI_v}{dA}\), where \(dI_v\) is the luminous intensity of an element of the surface with the area \(dA\) of the orthogonal projection of this element on a plane perpendicular to the given direction.
Luminance is a photometric measure of the luminous intensity per unit area of light travelling in a given direction. It describes the amount of light that passes through or is emitted from a particular area, and falls within a given solid angle.
L_v
Luminance
\(J \cdot T^3 \cdot U/L^2 \cdot M\)
\(cd \cdot s^3/kg \cdot m^2\)
\(lm/w\)
\(K = \frac{\Phi_v}{\Phi}\), where \(\Phi_v\) is the luminous flux and \(\Phi\) is the corresponding radiant flux.
Luminous Efficacy is the ratio of luminous flux (in lumens) to power (usually measured in watts). Depending on context, the power can be either the radiant flux of the source's output, or it can be the total electric power consumed by the source.
Luminous Efficacy
http://www.iso.org/iso/catalogue_detail?csnumber=43012
"Luminous Emittance" is the luminous flux per unit area emitted from a surface.
M_v
Luminous Emmitance
\(Q_v = \int_{0}^{\Delta t}{\Phi_v}{dt}\), where \(\Phi_v\) is the luminous flux occurring during the time interval with duration \(\Delta t\).
Luminous Energy is the perceived energy of light. This is sometimes also called the quantity of light.
Q_v
Qv
Luminous Energy
https://en.wikipedia.org/wiki/Exposure_(photography)#Photometric_and_radiometric_exposure
Luminous Exposure is the time-integrated illuminance.
H_v
Hv
Luminous Exposure
\(J \cdot U\)
\(cd\)
http://dbpedia.org/resource/Luminous_flux
http://en.wikipedia.org/wiki/Luminous_flux
http://www.iso.org/iso/catalogue_detail?csnumber=43012
\(\Phi_v = K_m \int_{0}^{\infty}{\Phi_\lambda(\lambda)}{V(\lambda)d\lambda}\), where \(K_m\) is the maximum spectral luminous efficacy, \(\Phi_\lambda(\lambda)\) is the spectral radiant flux, \(V(\lambda)\) is the spectral luminous efficiency, and \(\lambda\) is the wavelength.
Luminous Flux or Luminous Power is the measure of the perceived power of light. It differs from radiant flux, the measure of the total power of light emitted, in that luminous flux is adjusted to reflect the varying sensitivity of the human eye to different wavelengths of light.
F
Luminous Flux
In photometry, illuminance is the total luminous flux incident on a surface, per unit area. It is a measure of how much the incident light illuminates the surface, wavelength-weighted by the luminosity function to correlate with human brightness perception. Similarly, luminous emittance is the luminous flux per unit area emitted from a surface. In SI derived units these are measured in \(lux (lx)\) or \(lumens per square metre\) (\(cd \cdot m^{-2}\)). In the CGS system, the unit of illuminance is the \(phot\), which is equal to \(10,000 lux\). The \(foot-candle\) is a non-metric unit of illuminance that is used in photography.
\(J \cdot U/L^2\)
\(cd/m^2\)
http://en.wikipedia.org/wiki/Illuminance
Luminous Flux per Area
\(J\)
\(cd\)
http://dbpedia.org/resource/Luminous_intensity
Luminous Intensity is a measure of the wavelength-weighted power emitted by a light source in a particular direction per unit solid angle. The weighting is determined by the luminosity function, a standardized model of the sensitivity of the human eye to different wavelengths.
J
Luminous Intensity
The minimum mass a propulsive system can deliver to a specified target or location. Most mass- delivered requirements have associated Delta-V requirements, effectively specifying the path between the two points.
Mass Delivered
A factor applied to basic mass at the lowest level of design detail available based on type and maturity of hardware according to an approved MGA depletion schedule.
Mass Growth Allowance
MGA
Requirement minus predicted value. Margin is used as a metric in risk management. Positive margin mitigates the risk of mass increases from requirements maturation and implementation, underestimated predicted system, or subsystem mass.
Mass Margin
Variation in predicted MP due to lack of definition, manufacturing variations, environment effects, or accuracy limitation of measuring devices.
Mass Property Uncertainty
The rotational inertia or resistance to change in direction or speed of rotation about a defined axis.
I_{y}
Moment of Inertia in the Y axis
MOI
The rotational inertia or resistance to change in direction or speed of rotation about a defined axis.
I_{z}
Moment of Inertia in the Z axis
MOI
http://dbpedia.org/resource/Mach_number
"Mach Number" is a dimensionless quantity representing the speed of an object moving through air or other fluid divided by the local speed of sound. It is commonly used to represent the speed of an object when it is traveling close to or above the speed of sound. The Mach number is commonly used both with objects traveling at high speed in a fluid, and with high-speed fluid flows inside channels such as nozzles, diffusers or wind tunnels. As it is defined as a ratio of two speeds, it is a dimensionless number.
http://www.iso.org/iso/catalogue_detail?csnumber=31896
\(Ma = \frac{v_o}{c_o}\), where \(v_0\) is speed, and \(c_o\) is speed of sound.
http://www.iso.org/iso/catalogue_detail?csnumber=31896
"Mach Number" is a dimensionless quantity representing the speed of an object moving through air or other fluid divided by the local speed of sound. It is commonly used to represent the speed of an object when it is traveling close to or above the speed of sound. The Mach number is commonly used both with objects traveling at high speed in a fluid, and with high-speed fluid flows inside channels such as nozzles, diffusers or wind tunnels. As it is defined as a ratio of two speeds, it is a dimensionless number.
Ma
Mach Number
http://en.wikipedia.org/wiki/Cross_section_(physics)
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(\sum = n_1\sigma_1 + \cdots + n_j\sigma_j +\), where \(n_j\) is the number density and \(\sigma_j\) the cross-section for entities of type \(j\).
\(\sum\)
"Macroscopic Cross-section" is the sum of the cross-sections for a reaction or process of a specified type over all atoms or other entities in a given 3D domain, divided by the volume of that domain.
Macroscopic Cross-section
http://en.wikipedia.org/wiki/Cross_section_(physics)
http://en.wikipedia.org/wiki/Nuclear_cross_section
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(\sum_{tot}, \sum_T\)
"Macroscopic Total Cross-section" is the total cross-sections for all atoms or other entities in a given 3D domain, divided by the volume of that domain.
Macroscopic Total Cross-section
http://en.wikipedia.org/wiki/Madelung_constant
http://www.iso.org/iso/catalogue_detail?csnumber=31897
For a uni-univalent ionic crystal of specified structure, the binding energy \(V_b\) per pair of ions is \(V_b = \alpha\frac{e^2}{4\pi \varepsilon_0 a}\), where \(e\) is the elementary charge, \(\varepsilon_0\) is the electric constant, and \(a\) is the lattice constant which should be specified.
\(\alpha\)
"Madelung Constant" is used in determining the electrostatic potential of a single ion in a crystal by approximating the ions by point charges. It is named after Erwin Madelung, a German physicist.
Madelung Constant
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=121-11-49
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(m = I e_n A\), where \(I\) is electric current in a small closed loop, \(e_n\) is a unit vector perpendicular to the loop, and \(A\) is the area of the loop. The magnetic moment of a substance within a domain is the vector sum of the magnetic moments of all entities included in the domain.
"Magnetic Area Moment", for a magnetic dipole, is a vector quantity equal to the product of the current, the loop area, and the unit vector normal to the loop plane, the direction of which corresponds to the loop orientation. "Magnetic Area Moment" is also referred to as "Magnetic Moment".
m
Magnetic Area Moment
"Magnetic Dipole Moment" is the magnetic moment of a system is a measure of the magnitude and the direction of its magnetism. Magnetic moment usually refers to its Magnetic Dipole Moment, and quantifies the contribution of the system's internal magnetism to the external dipolar magnetic field produced by the system (that is, the component of the external magnetic field that is inversely proportional to the cube of the distance to the observer). The Magnetic Dipole Moment is a vector-valued quantity. For a particle or nucleus, vector quantity causing an increment \(\Delta W = -\mu \cdot B\) to its energy \(W\) in an external magnetic field with magnetic flux density \(B\).
\(A \cdot m^2\)
\(I \cdot L^2\)
http://dbpedia.org/resource/Magnetic_moment
http://en.wikipedia.org/wiki/Magnetic_moment
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=121-11-55
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
http://www.iso.org/iso/catalogue_detail?csnumber=31894
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(E_m = -m \cdot B\), where \(E_m\) is the interaction energy of the molecule with magnetic diploe moment \(m\) and a magnetic field with magnetic flux density \(B\)
or,
\(J_m = \mu_0 M\) where \(\mu_0\) is the magnetic constant and \(M\) is Magnetization.
\(\mu\)
J_m
Magnetic Dipole Moment
The Magnetic Field, denoted \(B\), is a fundamental field in electrodynamics which characterizes the magnetic force exerted by electric currents. It is closely related to the auxillary magnetic field H (see quantitykind:AuxillaryMagneticField).
\(M/I \cdot T^2\)
\(kg/A \cdot s^2\)
B
Magnetic Field
\(\textbf{Magnetic Field Strength}\) is a vector quantity obtained at a given point by subtracting the magnetization \(M\) from the magnetic flux density \(B\) divided by the magnetic constant \(\mu_0\). The magnetic field strength is related to the total current density \(J_{tot}\) via: \(\text{rot} H = J_{tot}\).
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=121-11-56
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(\mathbf{H} = \frac{\mathbf{B} }{\mu_0} - M\), where \(\mathbf{B} \) is magnetic flux density, \(\mu_0\) is the magnetic constant and \(M\) is magnetization.
\(\mathbf{H} \)
Magnetic Field Strength
\(L^2 \cdot M/I \cdot T^2\)
\(kg \cdot m^2/A \cdot s^2\)
http://dbpedia.org/resource/Magnetic_flux
\(magnetic-flux\)
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
http://www.oxfordreference.com/view/10.1093/acref/9780199233991.001.0001/acref-9780199233991-e-1800
\(\Phi = \int_S B \cdot e_n d A\), over a surface \(S\), where \(B\) is magnetic flux density and \(e_n dA\) is the vector surface element.
\(\Phi\)
\(\phi\)
"Magnetic Flux" is the product of the average magnetic field times the perpendicular area that it penetrates.
Magnetic Flux
"Magnetic Flux Density" is a vector quantity and is the magnetic flux per unit area of a magnetic field at right angles to the magnetic force. It can be defined in terms of the effects the field has, for example by \(B = F/q v \sin \theta\), where \(F\) is the force a moving charge \(q\) would experience if it was travelling at a velocity \(v\) in a direction making an angle θ with that of the field. The magnetic field strength is also a vector quantity and is related to \(B\) by: \(H = B/\mu\), where \(\mu\) is the permeability of the medium.
\(kg/A \cdot s^2\)
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
http://www.oxfordreference.com/view/10.1093/acref/9780199233991.001.0001/acref-9780199233991-e-1798
\(\mathbf{F} = qv \times B\), where \(F\) is force and \(v\) is velocity of any test particle with electric charge \(q\).
B
Magnetic flux density
\(L \cdot M/I \cdot T^2\)
\(kg \cdot m/A \cdot s^2\)
"Magnetic Flux per Unit Length" is a quantity in the SI and C.G.S. Systems of Quantities.
Magnetic flux per unit length
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=121-11-49
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(m = I e_n A\), where \(I\) is electric current in a small closed loop, \(e_n\) is a unit vector perpendicular to the loop, and \(A\) is the area of the loop. The magnetic moment of a substance within a domain is the vector sum of the magnetic moments of all entities included in the domain.
"Magnetic Moment", for a magnetic dipole, is a vector quantity equal to the product of the current, the loop area, and the unit vector normal to the loop plane, the direction of which corresponds to the loop orientation. "Magnetic Moment" is also referred to as "Magnetic Area Moment".
m
Magnetic Moment
\(\textbf{Magnetic Polarization}\) is a vector quantity equal to the product of the magnetization \(M\) and the magnetic constant \(\mu_0\).
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=121-11-54
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(J_m = \mu_0 M\), where \(\mu_0\) is the magentic constant and \(M\) is magnetization.
\(J_m\)
Magnetic Polarization
http://en.wikipedia.org/wiki/Quantum_number
http://www.iso.org/iso/catalogue_detail?csnumber=31894
The "Magnetic Quantum Number" describes the specific orbital (or "cloud") within that subshell, and yields the projection of the orbital angular momentum along a specified axis.
m
Magnetic Quantum Number
\(A \cdot s^2/kg \cdot m\)
\(I \cdot T^2/L \cdot M\)
http://en.wikipedia.org/wiki/Permeability_(electromagnetism)
"Length Per Unit Magnetic Flux} is the the resistance of a material to the establishment of a magnetic field in it. It is the reciprocal of \textit{Magnetic Permeability", the inverse of the measure of the ability of a material to support the formation of a magnetic field within itself.
Magnetic Reluctivity
"Magnetic Susceptability" is a scalar or tensor quantity the product of which by the magnetic constant \(\mu_0\) and by the magnetic field strength \(H\) is equal to the magnetic polarization \(J\). The definition given applies to an isotropic medium. For an anisotropic medium permeability is a second order tensor.
\(\kappa = \frac{M}{H}\)
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=121-12-37
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(\kappa = \frac{M}{H}\), where \(M\) is magnetization, and \(H\) is magnetic field strength.
\(\kappa\)
Magnetic Susceptability
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=121-11-57
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(U_m = \int_{r_a(C)}^{r_b} \mathbf{H} \cdot dr\), where \(\mathbf{H}\) is magnetic field strength and \(r\) is the position vector along a given curve \(C\) from point \(a\) to point \(b\).
"Magnetic Tension} is a scalar quantity equal to the line integral of the magnetic field strength \mathbf{H" along a specified path linking two points a and b.
U_m
Magnetic Tension
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=121-11-23
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(B = \textbf{rot} A\), where \(B\) is magnetic flux density.
"Magnetic Vector Potential" is the vector potential of the magnetic flux density. The magnetic vector potential is not unique since any irrotational vector field quantity can be added to a given magnetic vector potential without changing its rotation. Under static conditions the magnetic vector potential is often chosen so that its divergence is zero.
A
Magnetic Vector Potential
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=121-11-52
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(M = dm/dV\), where \(m\) is magentic moment of a substance in a domain with Volume \(V\).
"Magnetization" is defined as the ratio of magnetic moment per unit volume. It is a vector-valued quantity.
H_i
M
Magnetization
The Magnetization Field is defined as the ratio of magnetic moment per unit volume. It is a vector-valued quantity.
M
Magnetization Field
\(\textbf{Magnetomotive Force}\) (\(mmf\)) is the ability of an electric circuit to produce magnetic flux. Just as the ability of a battery to produce electric current is called its electromotive force or emf, mmf is taken as the work required to move a unit magnet pole from any point through any path which links the electric circuit back the same point in the presence of the magnetic force produced by the electric current in the circuit. \(\textbf{Magnetomotive Force}\) is the scalar line integral of the magnetic field strength along a closed path.
\(A\)
\(I \cdot U\)
http://dbpedia.org/resource/Magnetomotive_force
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=121-11-60
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(F_m = \oint \mathbf{H} \cdot dr\), where \(\mathbf{H}\) is magnetic field strength and \(r\) is position vector along a given curve \(C\) from point \(a\) to point \(b\).
\(F_m \)
Magnetomotive Force
In physics, mass, more specifically inertial mass, can be defined as a quantitative measure of an object's resistance to acceleration. The SI unit of mass is the kilogram (\(kg\))
\(M\)
\(kg\)
http://dbpedia.org/resource/Mass
http://en.wikipedia.org/wiki/Mass
m
Mass
\(a_m = \frac{a}{\rho}\), where \(a\) is the linear absorption coefficient and \(\rho\) is the mass density of the medium.
\(a_m\)
The mass absorption coefficient is the linear absorption coefficient divided by the density of the absorber.
Mass Absorption Coefficient
Mass Amount of Substance
Mass Amount of Substance Temperature
http://en.wikipedia.org/wiki/Mass_attenuation_coefficient
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(\mu_m = \frac{\mu}{\rho}\), where \(\mu\) is the linear attenuation coefficient and \(\rho\) is the mass density of the medium.
\(\mu_m\)
"Mass Attenuation Coefficient" is a measurement of how strongly a chemical species or substance absorbs or scatters light at a given wavelength, per unit mass.
Mass Attenuation Coefficient
http://en.wikipedia.org/wiki/Mass_concentration_(chemistry)
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(\rho_B = \frac{m_B}{V}\), where \(m_B\) is the mass of substance \(B\) and \(V\) is the volume.
\(\rho_B\)
The "Mass Concentration" of substance B is defined as the mass of a constituent divided by the volume of the mixture .
Mass Concentration
http://www.iso.org/iso/catalogue_detail?csnumber=31890
\(w = m/V\), where \(m\) is mass of water, irrespective of the form of aggregation, and \(V\) is volume. Mass concentration of water at saturation is denoted \(w_{sat}\).
"Mass Concentration of Water Valour} is one of a number of \textit{Concentration" quantities defined by ISO 8000.
w
Mass Concentration of Water
http://www.iso.org/iso/catalogue_detail?csnumber=31890
\(w = m/V\), where \(m\) is mass of water vapour and \(V\) is total gas volume. Mass concentration of water vapour at saturation is denoted \(v_{sat}\).
"Mass Concentration of Water} is one of a number of \textit{Concentration" quantities defined by ISO 8000.
v
Mass Concentration of Water Vapour
http://en.wikipedia.org/wiki/Binding_energy
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(B = Zm(^{1}\textrm{H}) + Nm_n - m_a\), where \(Z\) is the proton number of the atom, \(m(^{1}\textrm{H})\) is atomic mass of \(^{1}\textrm{H}\), \(N\) is the neutron number, \(m_n\) is the rest mass of the neutron, and \(m_a\) is the rest mass of the atom.
The "Mass Defect", also termed mass deficit, or mass packing fraction, describes mass change (decrease) in bound systems, particularly atomic nuclei.
B
Mass Defect
\(kg m^{-3}\)
http://en.wikipedia.org/wiki/Density
http://www.iso.org/iso/catalogue_detail?csnumber=31889
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(\rho = \frac{dm}{dV}\), where \(m\) is mass and \(V\) is volume.
\(\rho\)
The mass density or density of a material is its mass per unit volume.
Mass Density
http://physics.nist.gov/PhysRefData/XrayMassCoef/chap3.html
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(\frac{\mu_{tr}}{\rho} = -\frac{1}{\rho}\frac{1}{R}\frac{dR_{tr}}{dl}\), where \(dR_{tr}\) is the mean energy that is transferred to kinetic energy of charged particles by interactions of the incident radiation \(R\) in traversing a distance \(dl\) in the material of density \(\rho\).
\(\frac{\mu_{tr}}{\rho}\)
"Mass Energy Transfer Coefficient" is that fraction of the mass attenuation coefficient which contributes to the production of kinetic energy in charged particles.
Mass Energy Transfer Coefficient
http://en.wikipedia.org/wiki/Mass_excess
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(\Delta = m_a - Am_u\), where \(m_a\) is the rest mass of the atom, \(A\) is its nucleon number, and \(m_u\) is the unified atomic mass constant.
\(\Delta\)
The "Mass Excess" of a nuclide is the difference between its actual mass and its mass number in atomic mass units. It is one of the predominant methods for tabulating nuclear mass.
Mass Excess
"Mass Flow Rate" is a measure of Mass flux. The common symbol is \(\dot{m}\) (pronounced "m-dot"), although sometimes \(\mu\) is used. The SI units are \(kg s-1\).
\(kg sec^{-1}\)
http://dbpedia.org/resource/Mass_flow_rate
http://en.wikipedia.org/wiki/Mass_flow_rate
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(q_m = \frac{dm}{dt}\), where \(m\) is mass and \(t\) is time.
\(\dot{m}\)
q_m
Mass Flow Rate
http://en.wikipedia.org/wiki/Mass_fraction_(chemistry)
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(w_B = \frac{m_B}{m}\), where \(m_B\) is the mass of substance \(B\) and \(m\) is the total.
The "Mass Fraction" is the fraction of one substance with mass to the mass of the total mixture .
w_B
Mass Fraction
http://www.iso.org/iso/catalogue_detail?csnumber=31890
\(w_d= 1 - w_{h2o}\), where \(w_{h2o}\) is mass fraction of water.
"Mass Fraction of Dry Matter} is one of a number of \textit{Concentration" quantities defined by ISO 8000.
w_d
Mass Fraction of Dry Matter
http://www.iso.org/iso/catalogue_detail?csnumber=31890
\(w_{H_2o} = \frac{u}{1+u}\), where \(u\) is mass ratio of water to dry water.
"Mass Fraction of Water} is one of a number of \textit{Concentration" quantities defined by ISO 8000.
w_{H_2o}
Mass Fraction of Water
The "Mass Number" (A), also called atomic mass number or nucleon number, is the total number of protons and neutrons (together known as nucleons) in an atomic nucleus. Nuclides with the same value of \(A\) are called isobars.
http://en.wikipedia.org/wiki/Mass_number
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(A = Z + N\), where \(Z\) is the atomic number and \(N\) is the neutron number.
A
Mass Number
M_{E}
Mass Of Electrical Power Supply
M_{SB}
Mass Of Solid Booster
\(M_{\oplus}\)
Earth mass is the unit of mass equal to that of the Earth. Earth mass is often used to describe masses of rocky terrestrial planets.
Mass Of The Earth
The area density (also known as areal density, surface density, or superficial density) of a two-dimensional object is calculated as the mass per unit area. The SI derived unit is: kilogram per square metre (\(kg \cdot m^{-2}\)).
\(M/L^2\)
\(kg/m^2\)
http://en.wikipedia.org/wiki/Area_density
\(\rho_A = \frac {m} {A}\)
\(\rho_A \)
Mass per Area
In Physics and Engineering, mass flux is the rate of mass flow per unit area. The common symbols are \(j\), \(J\), \(\phi\), or \(\Phi\) (Greek lower or capital Phi), sometimes with subscript \(m\) to indicate mass is the flowing quantity. Its SI units are \( kg s^{-1} m^{-2}\).
\(M/L^2 \cdot T\)
\(kg/m^2 \cdot s\)
http://en.wikipedia.org/wiki/Mass_flux
\(j_m = \lim\limits_{A \rightarrow 0}\frac{I_m}{A}\)
Mass per Area Time
The mass-to-charge ratio ratio (\(m/Q\)) is a physical quantity that is widely used in the electrodynamics of charged particles, for example, in electron optics and ion optics. The importance of the mass-to-charge ratio, according to classical electrodynamics, is that two particles with the same mass-to-charge ratio move in the same path in a vacuum when subjected to the same electric and magnetic fields. Its SI units are \(kg/C\), but it can also be measured in Thomson (\(Th\)).
\(M/I \cdot T\)
\(kg/A \cdot s\)
http://en.wikipedia.org/wiki/Mass-to-charge_ratio
Mass per Electric Charge
Linear density, linear mass density or linear mass is a measure of mass per unit of length, and it is a characteristic of strings or other one-dimensional objects. The SI unit of linear density is the kilogram per metre (\(kg/m\)).
\(M/L\)
\(kg/m\)
http://en.wikipedia.org/wiki/Linear_density
\(\mu\)
Mass per Length
\(M/T\)
\(kg/s\)
Mass per Time
In aerospace engineering, mass ratio is a measure of the efficiency of a rocket. It describes how much more massive the vehicle is with propellant than without; that is, it is the ratio of the rocket's wet mass (vehicle plus contents plus propellant) to its dry mass (vehicle plus contents)
R or M_{R}
Mass Ratio
http://www.iso.org/iso/catalogue_detail?csnumber=31890
\(u = m/m_d\), where \(m\) is mass of water vapour and \(m_d\) is mass of dry matter. Mass ratio of water to dry matter at saturation is denoted \(u_{sat}\).
"Mass Ratio of Water to Dry Matter} is one of a number of \textit{Concentration Ratio" quantities defined by ISO 8000.
u
Mass Concentration of Water To Dry Matter
http://www.iso.org/iso/catalogue_detail?csnumber=31890
\(x = m/m_d\), where \(m\) is mass of water vapour and \(m_d\) is mass of dry gas. Mass ratio of water vapour to dry gas at saturation is denoted \(x_{sat}\).
"Mass Ratio of Water Vapour to Dry Gas} is one of a number of \textit{Concentration Ratio" quantities defined by ISO 8000.
x
Mass Ratio of Water Vapour to Dry Gas
\(K \cdot kg\)
\(\Theta \cdot M\)
Mass Temperature
http://www.encyclo.co.uk/define/massic%20activity
http://www.iso.org/iso/catalogue_detail?csnumber=43012
"Massic Activity" is the activity divided by the total mass of the sample.
a
Massic Activity
The Massieu function, \(\Psi\), is defined as: \(\Psi = \Psi (X_1, \dots , X_i, Y_{i+1}, \dots , Y_r )\), where for every system with degree of freedom \(r\) one may choose \(r\) variables, e.g. , to define a coordinate system, where \(X\) and \(Y\) are extensive and intensive variables, respectively, and where at least one extensive variable must be within this set in order to define the size of the system. The \((r + 1)^{th}\) variable,\(\Psi\) , is then called the Massieu function.
http://en.wikipedia.org/wiki/Massieu_function
http://www.iso.org/iso/catalogue_detail?csnumber=31890
\(J = -A/T\), where \(A\) is Helmholtz energy and \(T\) is thermodynamic temperature.
J
Massieu Function
Maximum Expected Operating Thrust
MEOT
Max Operating Thrust
MOT
Max Sea Level thrust (Mlbf)
Max Sea Level Thrust
http://www.iso.org/iso/catalogue_detail?csnumber=31895
"Maximum Beta-Particle Energy" is the maximum energy of the energy spectrum in a beta-particle disintegration process.
Eᵦ
Maximum Beta-Particle Energy
Maximum Expected Operating Pressure
MEOP
MOP
Maximum Operating Pressure
http://www.answers.com/topic/energy-imparted
To the matter in a given domain, \(\bar{\varepsilon} = R_{in} - R_{out} + \sum Q\), where \(R_{in}\) is the radiant energy of all those charged and uncharged ionizing particles that enter the domain, \(R_{out}\) is the radiant energy of all those charged and uncharged ionizing particles that leave the domain, and \(\sum Q\) is the sum of all changes of the rest energy of nuclei and elementary particles that occur in that domain.
http://www.iso.org/iso/catalogue_detail?csnumber=31895
The "Mean Energy Imparted", is the average energy imparted to irradiated matter.
ε̅
Mean Energy Imparted
m
http://en.wikipedia.org/wiki/Mean_free_path
http://www.iso.org/iso/catalogue_detail?csnumber=31894
http://www.iso.org/iso/catalogue_detail?csnumber=31895
"Mean Free Path" is the average distance travelled by a moving particle (such as an atom, a molecule, a photon) between successive impacts (collisions) which modify its direction or energy or other particle properties.
λ
Mean Free Path
The "Mean Lifetime" is the average length of time that an element remains in the set of discrete elements in a decaying quantity, \(N(t)\).
http://en.wikipedia.org/wiki/Exponential_decay
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(\tau = \frac{1}{\lambda}\), where \(\lambda\) is the decay constant.
\(\tau\)
Mean Lifetime
http://goldbook.iupac.org/M03782.html
http://www.iso.org/iso/catalogue_detail?csnumber=31895
"Mean Linear Range" is, in a given material, for specified charged particles of a specified energy, the average displacement of the particles before they stop. That is, the mean totl rectified path length travelled by a particle in the course of slowing down to rest (or to some suitable cut-off energy) in a given substance under specified conditions averaged over a group of particles having the same initial energy.
R
Mean Linear Range
http://goldbook.iupac.org/M03783.html
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(R_\rho = R\rho\), where \(R\) is the mean linear range and \(\rho\) is the mass density of the sample.
\(R_\rho\)
"Mean Mass Range" is the mean linear range multiplied by the mass density of the material.
Mean Mass Range
http://dbpedia.org/resource/Mechanical_energy
http://en.wikipedia.org/wiki/Mechanical_energy
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(E = T + V\), where \(T\) is kinetic energy and \(V\) is potential energy.
Mechanical Energy is the sum of potential energy and kinetic energy. It is the energy associated with the motion and position of an object.
E
Mechanical Energy
Mechanical Impedance
Mechanical Mobility
\(Z_m = Z_a A^2\), where \(A\) is the area of the surface considered and \(Z_a\) is the acoustic impedance.
Mechanical surface impedance at a surface, is the complex quotient of the total force on the surface by the component of the average sound particle velocity at the surface in the direction of the force
Z
belongs to SOQ-ISO
Mechanical surface impedance
http://en.wikipedia.org/wiki/Microcanonical_ensemble
http://en.wikipedia.org/wiki/Partition_function_(statistical_mechanics)#Grand_canonical_partition_function
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(\Omega = \sum_r 1\), where the sum is over all quantum states consistent with given energy. volume, external fields, and content.
\(\Omega\)
A "Micro Canonical Partition Function" applies to a micro canonical ensemble, in which the system is allowed to exchange heat with the environment at fixed temperature, volume, and a fixed number of particles.
Micro Canonical Partition Function
Microbial Formation
http://encyclopedia2.thefreedictionary.com/migration+area
http://www.iso.org/iso/catalogue_detail?csnumber=31895
"Migration Area" is the sum of the slowing-down area from fission energy to thermal energy and the diffusion area for thermal neutrons.
M^2
Migration Area
http://encyclopedia2.thefreedictionary.com/migration+area
\(M = \sqrt{M^2}\), where \(M^2\) is the migration area.
http://www.iso.org/iso/catalogue_detail?csnumber=31895
"Migration Length" is the square root of the migration area.
M
Migration Length
http://en.wikipedia.org/wiki/Electron_mobility
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(\mu\)
"Mobility" characterizes how quickly a particle can move through a metal or semiconductor, when pulled by an electric field. The average drift speed imparted to a charged particle in a medium by an electric field, divided by the electric field strength.
Mobility
http://baervan.nmt.edu/research_groups/reservoir_sweep_improvement/pages/clean_up/mobility.html
http://www.iso.org/iso/catalogue_detail?csnumber=31897
\(b = \frac{\mu_n}{\mu_p}\), where \(\mu_n\) and \(\mu_p\) are mobilities for electrons and holes, respectively.
"MobilityRatio" describes permeability of a porous material to a given phase divided by the viscosity of that phase.
b
Mobility Ratio
http://en.wikipedia.org/wiki/Absolute_value
http://en.wikipedia.org/wiki/Admittance
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=131-12-51
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(Y = \left | \underline{Y} \right |\), where \(\underline{Y}\) is admittance.
"Modulus Of Admittance" is the absolute value of the quantity "admittance".
Y
Modulus Of Admittance
http://en.wikipedia.org/wiki/Elastic_modulus
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(E = \frac{\sigma}{\varepsilon}\), where \(\sigma\) is the normal stress and \(\varepsilon\) is the linear strain.
The Modulus of Elasticity is the mathematical description of an object or substance's tendency to be deformed elastically (that is, non-permanently) when a force is applied to it.
E
Modulus of Elasticity
"Modulus Of Impedance} is the absolute value of the quantity \textit{impedance". Apparent impedance is defined more generally as
the quotient of rms voltage and rms electric current; it is often denoted by \(Z\).
http://en.wikipedia.org/wiki/Absolute_value
http://en.wikipedia.org/wiki/Electrical_impedance
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(Z = \left | \underline{Z} \right |\), where \(\underline{Z}\) is impedance.
Z
Modulus Of Impedance
http://en.wikipedia.org/wiki/Molality
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(b_B = \frac{n_B}{m_a}\), where \(n_B\) is the amount of substance and \(m_A\) is the mass.
The "Molality of Solute" of a solution is defined as the amount of substance of solute divided by the mass in kg of the solvent.
b_B
Molality of Solute
\(x = aV_m\), where \(a\) is the linear absorption coefficient and \(V_m\) is the molar volume.
"Molar Absorption Coefficient" is a spectrophotometric unit indicating the light a substance absorbs with respect to length, usually centimeters, and concentration, usually moles per liter.
x
Molar Absorption Coefficient
\(L^2 \cdot M/M \cdot T\)
\(kg \cdot m^2/mol \cdot s\)
http://cvika.grimoar.cz/callen/callen_21.pdf
Molar Angular Momentum
http://en.wikipedia.org/wiki/Mass_attenuation_coefficient
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(\mu_c = -\frac{\mu}{c}\), where \(\mu\) is the linear attenuation coefficient and \(c\) is the amount-of-substance concentration.
\(\mu_c\)
"Molar Attenuation Coefficient" is a measurement of how strongly a chemical species or substance absorbs or scatters light at a given wavelength, per amount of substance.
Molar Attenuation Coefficient
http://en.wikipedia.org/wiki/Molar_conductivity
http://encyclopedia2.thefreedictionary.com/molar+conductivity
\(\Gamma_m = \frac{x}{c_B}\), where \(x\) is the electrolytic conductivity and \(c_B\) is the amount-of-substance concentration.
\(\Gamma_m\)
"Molar Conductivity" is the conductivity of an electrolyte solution divided by the molar concentration of the electrolyte, and so measures the efficiency with which a given electrolyte conducts electricity in solution.
Molar Conductivity
"Molar Energy" is the total energy contained by a thermodynamic system. The unit is \(J/mol\), also expressed as \(joule/mole\), or \(joules per mole\). This unit is commonly used in the SI unit system. The quantity has the dimension of \(M \cdot L^2 \cdot T^{-2} \cdot N^{-1}\) where \(M\) is mass, \(L\) is length, \(T\) is time, and \(N\) is amount of substance.
\(L^2 \cdot M/N \cdot T^2\)
\(kg \cdot m^2/mol \cdot s^2\)
http://www.efunda.com/glossary/units/units-molar_energy-joule_per_mole.cfm
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(U_m = \frac{U}{n}\), where \(U\) is internal energy and \(n\) is amount of substance.
U_M
dimensions are wrong
Molar Energy
http://en.wikipedia.org/wiki/Standard_molar_entropy
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(S_m = \frac{S}{n}\), where \(S\) is entropy and \(n\) is amount of substance.
The "Standard Molar Entropy" is the entropy content of one mole of substance, under standard conditions (not standard temperature and pressure STP).
S_m
Molar Entropy
\(mol sec^{-1}\)
https://www.sciencedirect.com/topics/engineering/molar-flow-rate
Molar Flow Rate is a measure of the amount of substance (the number of molecules) that passes through a given area perpendicular to the flow in a given time. Typically this area is constrained, for example a section through a pipe, but it could also apply to an open flow.
q_V
Molar Flow Rate
\(L^2 \cdot M/\Theta \cdot M \cdot T^2\)
\(kg \cdot m^2/K \cdot mol \cdot s^2\)
http://chemistry.about.com/od/chemistryglossary/g/Molar-Heat-Capacity-Definition.htm
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(C_m = \frac{C}{n}\), where \(C\) is heat capacity and \(n\) is amount of substance.
"Molar Heat Capacity" is the amount of heat energy required to raise the temperature of 1 mole of a substance. In SI units, molar heat capacity (symbol: cn) is the amount of heat in joules required to raise 1 mole of a substance 1 Kelvin.
C_m
cn
Molar Heat Capacity
In chemistry, the molar mass M is defined as the mass of a given substance (chemical element or chemical compound) divided by its amount of substance. It is a physical property of a given substance. The base SI unit for molar mass is \(kg/mol\).
\(M/M\)
\(kg/mol\)
http://dbpedia.org/resource/Molar_mass
http://en.wikipedia.org/wiki/Molar_mass
http://www.iso.org/iso/catalogue_detail?csnumber=31894
M
Molar Mass
http://goldbook.iupac.org/O04313.html
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(\alpha_n = \alpha \frac{A}{n}\), where \(\alpha\) is the angle of optical rotation, and \(n\) is the amount of substance of the optically active component in the path of a linearly polarized light beam of cross sectional area \(A\).
\(\alpha_n\)
The "Molar Optical Rotatory Power" Angle of optical rotation divided by the optical path length through the medium and by the amount concentration giving the molar optical rotatory power.
Molar Optical Rotatory Power
The molar volume, symbol \(V_m\), is the volume occupied by one mole of a substance (chemical element or chemical compound) at a given temperature and pressure. It is equal to the molar mass (\(M\)) divided by the mass density (\(\rho\)). It has the SI unit cubic metres per mole (\(m^{1}/mol\)). For ideal gases, the molar volume is given by the ideal gas equation: this is a good approximation for many common gases at standard temperature and pressure. For crystalline solids, the molar volume can be measured by X-ray crystallography.
\(L^3/M\)
\(m^3/mol\)
http://dbpedia.org/resource/Molar_volume
http://en.wikipedia.org/wiki/Molar_volume
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(V_m = \frac{V}{n}\), where \(V\) is volume and \(n\) is amount of substance.
V_m
Molar Volume
http://dbpedia.org/resource/Mole_fraction
In chemistry, the mole fraction of a component in a mixture is the relative proportion of molecules belonging to the component to those in the mixture, by number of molecules. It is one way of measuring concentration.
Mole Fraction
m^{-3}
http://en.wikipedia.org/wiki/Molar_concentration
\(C_B = \frac{N_B}{V}\), where \(N_B\) is the number of molecules of \(B\) and \(V\) is the volume.
http://www.iso.org/iso/catalogue_detail?csnumber=31894
The "Molecular Concentration" of substance B is defined as the number of molecules of B divided by the volume of the mixture
C_B
Molecular Concentration
http://dbpedia.org/resource/Molecular_mass
http://en.wikipedia.org/wiki/Molecular_mass#Relative_molecular_mass
http://www.iso.org/iso/catalogue_detail?csnumber=31894
The molecular mass, or molecular weight of a chemical compound is the mass of one molecule of that compound, relative to the unified atomic mass unit, u. Molecular mass should not be confused with molar mass, which is the mass of one mole of a substance.
M
Molecular Mass
http://oceanworld.tamu.edu/resources/ocng_textbook/chapter08/chapter08_01.htm
Molecules in a fluid close to a solid boundary sometime strike the boundary and transfer momentum to it. Molecules further from the boundary collide with molecules that have struck the boundary, further transferring the change in momentum into the interior of the fluid. This transfer of momentum is molecular viscosity. Molecules, however, travel only micrometers between collisions, and the process is very inefficient for transferring momentum even a few centimeters. Molecular viscosity is important only within a few millimeters of a boundary.
Molecular Viscosity
http://en.wikipedia.org/wiki/Moment_(physics)
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(M = r \cdot F\), where \(r\) is the position vector and \(F\) is the force.
Moment of force (often just moment) is the tendency of a force to twist or rotate an object.
M
Moment of Force
\(L^2 \cdot M\)
\(kg \cdot m^2\)
http://en.wikipedia.org/wiki/Moment_of_inertia
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(I_Q = \int r^2_Q dm\), where \(r_Q\) is the radial distance from a \(Q-axis\) and \(m\) is mass.
The rotational inertia or resistance to change in direction or speed of rotation about a defined axis.
I
Moment of Inertia
MOI
http://dbpedia.org/resource/Momentum
The momentum of a system of particles is given by the sum of the momentums of the individual particles which make up the system or by the product of the total mass of the system and the velocity of the center of gravity of the system. The momentum of a continuous medium is given by the integral of the velocity over the mass of the medium or by the product of the total mass of the medium and the velocity of the center of gravity of the medium.
p
http://en.wikipedia.org/wiki/Momentum
Momentum
Morbidity rate is a measure of the incidence of a disease in a particular population, scaled to the size of that population, per unit of time.
Morbidity Rate
https://en.wikipedia.org/wiki/Mortality_rate
Mortality rate, or death rate, is a measure of the number of deaths (in general, or due to a specific cause) in a particular population, scaled to the size of that population, per unit of time.
Mortality Rate
http://en.wikipedia.org/wiki/Neutron_multiplication_factor
http://www.iso.org/iso/catalogue_detail?csnumber=31895
The "Multiplication Factor" is the ratio of the total number of fission or fission-dependent neutrons produced in a time interval to the total number of neutrons lost by absorption and leakage during the same interval.
k
Multiplication Factor
\(\textit{Mutual Inductance}\) is the non-diagonal term of the inductance matrix. For two loops, the symbol \(M\) is used for \(L_{12}\).
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=131-12-36
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(L_{mn} = \frac{\Psi_m}{I_n}\), where \(I_n\) is an electric current in a thin conducting loop \(n\) and \(\Psi_m\) is the linked flux caused by that electric current in another loop \(m\).
L_{mn}
Mutual Inductance
The amount of propellant mass within a stage that is available for impulse for use in nominal payload performance prediction. This mass excludes loaded propellant that has been set aside for off- nominal performance behavior (FPR and fuel bias).
http://elib.dlr.de/68314/1/IAF10-D2.3.1.pdf
Nominal Ascent Propellant Mass
\(A_e(\lambda) = -ln(\tau(\lambda))\), where \(\tau\) is the transmittance at a given wavelength \(\lambda\).
Napierian Absorbance is the natural (Napierian) logarithm of the reciprocal of the spectral internal transmittance.
A_e, B
Napierian Absorbance
http://en.wikipedia.org/wiki/Néel_temperature
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Neel Temperature" is the critical thermodynamic temperature of an antiferromagnet.
T_C
Neel Temperature
http://encyclopedia2.thefreedictionary.com/Diffusion+of+Neutrons
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(D_n = -\frac{J_x}{\frac{\partial dn}{\partial dx}}\), where \(J_x\) is the \(x-component\) of the particle current and \(n\) is the particle number density.
The "Diffusion Coefficient" is
D
Diffusion Coefficient
The neutron diffusion length is equivalent to the relaxation length, that is, to the distance, in which the neutron flux decreases by a factor e
L_{r}
Neutron Diffusion Length
"Neutron Number", symbol \(N\), is the number of neutrons in a nuclide. Nuclides with the same value of \(N\) but different values of \(Z\) are called isotones. \(N - Z\) is called the neutron excess number.
http://en.wikipedia.org/wiki/Neutron_number
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31895
http://www.iso.org/iso/catalogue_detail?csnumber=31895
N
Neutron Number
http://en.wikipedia.org/wiki/Fission_product_yield
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(\eta\)
The "Neutron Yield per Absorption" is the average number of fission neutrons, both prompt and delayed, emitted per neutron absorbed in a fissionable nuclide or in a nuclear fuel, as specified.
Neutron Yield per Absorption
http://en.wikipedia.org/wiki/Fission_product_yield
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(\nu\)
The "Neutron Yield per Fission" is the average number of fission neutrons, both prompt and delayed, emitted per fission event.
Neutron Yield per Fission
http://en.wikipedia.org/wiki/Six_factor_formula
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(\Lambda\)
The "Non-Leakage Probability" is the probability that a neutron will not escape from the reactor during the slowing-down process or while it diffuses as a thermal neutron
Non-Leakage Probability
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=131-11-43
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(Q^{'} = \sqrt{{\left | \underline{S} \right |}^2 - P^2}\), where \(\underline{S}\) is apparent power and \(P\) is active power.
"Non-active Power", for a two-terminal element or a two-terminal circuit under periodic conditions, is the quantity equal to the square root of the difference of the squares of the apparent power and the active power.
Q'
Non-active Power
\(n m^{-2}\)
http://en.wikipedia.org/wiki/Stress_(mechanics)
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(\sigma = \frac{dF_n}{dA}\), where \(dF_n\) is the normal component of force and \(dA\) is the area of the surface element.
\(\sigma\)
Normal stress is defined as the stress resulting from a force acting normal to a body surface. Normal stress can be caused by several loading methods, the most common being axial tension and compression, bending, and hoop stress.
Normal Stress
Cross-sectional area of the nozzle at the throat.
A^*
Nozzle Throat Cross-sectional Area
Nozzle Throat Diameter
p^*
Nozzle Throat Pressure
F_R
Nozzle Walls Thrust Reaction
http://en.wikipedia.org/wiki/Nuclear_quadrupole_resonance
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(Q = (\frac{1}{e}) \int (3z^2 - r^2)\rho(x, y, z)dV\), in the quantum state with the nuclear spin in the field direction \((z)\), where \(\rho(x, y, z)\) is the nuclear electric charge density, \(e\) is the elementary charge, \(r^2 = x^2 + y^2 + z^2\), and \(dV\) is the volume element \(dx\) \(dy\) \(dz\).
"Nuclear Quadrupole Moment" is a quantity that characterizes the deviation from spherical symmetry of the electrical charge distribution in an atomic nucleus.
Q
Nuclear Quadrupole Moment
http://en.wikipedia.org/wiki/Atomic_nucleus
This quantity is not exactly defined. It is given approximately for nuclei in their ground state only by \(R = r_0 A^{\frac{1}{3}}\), where \(r_0 \approx 1.2 x 10^{-15} m\) and \(A\) is the nucleon number.
http://www.iso.org/iso/catalogue_detail?csnumber=31895
"Nuclear Radius" is the conventional radius of sphere in which the nuclear matter is included
R
Nuclear Radius
http://en.wikipedia.org/wiki/Quantum_number
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(I^2 = \hbar^2 I(I + 1)\), where \(\hbar\) is the Planck constant.
The "Spin Quantum Number" describes the spin (intrinsic angular momentum) of the electron within that orbital, and gives the projection of the spin angular momentum S along the specified axis
I
Spin Quantum Number
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31895
Number of nucleons in an atomic nucleus.A = Z+N. Nuclides with the same value of A are called isobars.
A
Nucleon number
mass-number
http://dbpedia.org/resource/Number_density
http://en.wikipedia.org/wiki/Number_density
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(n = \frac{N}{V}\), where \(N\) is the number of particles and \(V\) is volume.
In physics, astronomy, and chemistry, number density (symbol: n) is a kind of quantity used to describe the degree of concentration of countable objects (atoms, molecules, dust particles, galaxies, etc.) in the three-dimensional physical space.
n
Number Density
http://en.wikipedia.org/wiki/Particle_number
http://www.iso.org/iso/catalogue_detail?csnumber=31894
"Number of Particles", also known as the particle number, of a thermodynamic system, conventionally indicated with the letter N, is the number of constituent particles in that system.
N_B
Number of Particles
http://www.iso.org/iso/catalogue_detail?csnumber=43012
\(\overline{T_o}\)
"Olfactory Threshold" are thresholds for the concentrations of various classes of smell that can be detected.
Olfactory Threshold
Angular momentum of the orbit per unit mass of the vehicle
h
Orbital Angular Momentum per Unit Mass
The "Principal Quantum Number" describes the electron shell, or energy level, of an atom. The value of \(n\) ranges from 1 to the shell containing the outermost electron of that atom.
http://en.wikipedia.org/wiki/Quantum_number
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(l^2 = \hbar^2 l(l + 1), l = 0, 1, ..., n - 1\), where \(l_i\) refers to a specific particle \(i\).
l
Orbital Angular Momentum Quantum Number
r
Orbital Radial Distance
"Order of Reflection" is \(n\) in the Bragg's Law equation.
http://www.answers.com/topic/order-of-reflection
http://www.iso.org/iso/catalogue_detail?csnumber=31897
n
Order of Reflection
http://en.wikipedia.org/wiki/Osmotic_coefficient
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(\varphi = -(M_A\sum b_B)^{-1} \ln a_A\), where \(M_A\) is the molar mass of the solvent \(A\), \(\sum\) denotes summation over all the solutes, \(b_B\) is the molality of solute \(B\), and \(a_A\) is the activity of solvent \(A\).
\(\varphi\)
The "Osmotic Coefficient" is a quantity which characterises the deviation of a solvent from ideal behavior.
Osmotic Coefficient
http://en.wikipedia.org/wiki/Osmotic_pressure
\(\varphi = -(M_A\sum b_B)^{-1} \ln a_A\), where \(M_A\) is the molar mass of the solvent \(A\), \(\sum\) denotes summation over all the solutes, \(b_B\) is the molality of solute \(B\), and \(a_A\) is the activity of solvent \(A\).
http://www.iso.org/iso/catalogue_detail?csnumber=31894
The "Osmotic Pressure" is the pressure which needs to be applied to a solution to prevent the inward flow of water across a semipermeable membrane.
Π
Osmotic Pressure
Additional distance traveled by a rocket because Of excessive initial velocity.
s_i
Over-range distance
Sum of the basic mass and the MGA. Current prediction of the final mass based on the current requirements and design.
Predicted Mass
A measure of a body's dynamic (or coupled) imbalance resulting in a precession when rotating about an axis other than the body?s principal axis.
Product of Inertia
A measure of a body's dynamic (or coupled) imbalance resulting in a precession when rotating about an axis other than the body?s principal axis.
Product of Inertia in the X axis
A measure of a body?s dynamic (or coupled) imbalance resulting in a precession when rotating about an axis other than the body's principal axis.
Product of Inertia in the Y axis
A measure of a body's dynamic (or coupled) imbalance resulting in a precession when rotating about an axis other than the body's principal axis.
Product of Inertia in the Z axis
http://en.wikipedia.org/wiki/Atomic_packing_factor
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(f = \frac{\Delta_r}{A}\), where \(\Delta_r\) is the relative mass excess and \(A\) is the nucleon number.
The "Packing Fraction" is the fraction of volume in a crystal structure that is occupied by atoms.
f
Packing Fraction
pa
http://en.wikipedia.org/wiki/Partial_pressure
\(p_B = x_B \cdot p\), where \(x_B\) is the amount-of-substance fraction of substance \(B\) and \(p\) is the total pressure.
http://www.iso.org/iso/catalogue_detail?csnumber=31894
"Partial Pressure" is the pressure that the gas would have if it alone occupied the volume of the mixture at the same temperature.
p_B
Partial Pressure
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(\int J \cdot e_n dA = \frac{dN}{dt}\), where \(e_ndA\) is the vector surface element, \(N\) is the net number of particles passing over a surface, and \(dt\) describes the time interval.
"Particle Current" can be used to describe the net number of particles passing through a surface in an infinitesimal time interval.
J, S
Particle Current
http://en.wikipedia.org/wiki/Fluence
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(\Phi = \frac{dN}{dA}\), where \(dN\) describes the number of particles incident on a small spherical domain at a given point in space, and \(dA\) describes the cross-sectional area of that domain.
\(\Phi\)
"Particle Fluence" is the total number of particles that intersect a unit area in a specific time interval of interest, and has units of m–2 (number of particles per meter squared).
Particle Fluence
http://www.encyclo.co.uk/define/Fluence%20Rate
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(\theta = \frac{d\Phi}{dt}\), where \(d\Phi\) is the increment of the particle fluence during an infinitesimal time interval with duration \(dt\).
\(\theta\)
"Particle Fluence Rate" can be defined as the total number of particles (typically Gamma Ray Photons ) crossing over a sphere of unit cross section which surrounds a Point Source of Ionising Radiation.
Particle Fluence Rate
http://en.wikipedia.org/wiki/Particle_number#Particle_number_density
\(n = \frac{N}{V}\), where \(N\) is the number of particles in the 3D domain with the volume \(V\).
http://www.iso.org/iso/catalogue_detail?csnumber=31895
The "Particle Number Density" is obtained by dividing the particle number of a system by its volume.
n
Particle Number Density
http://en.wikipedia.org/wiki/Position_(vector)
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Particle Position Vector" is the position vector of a particle.
r, R
Particle Position Vector
http://www.iso.org/iso/catalogue_detail?csnumber=31895
"Particle Source Density" is the rate of production of particles in a 3D domain divided by the volume of that element.
S
Particle Source Density
http://en.wikipedia.org/wiki/Path_length
http://www.iso.org/iso/catalogue_detail?csnumber=43012
"PathLength" is
s
Path Length
Payload mass is the mass of the payload carried by the craft. In a multistage spacecraft the payload mass of the last stage is the mass of the payload and the payload masses of the other stages are considered to be the gross masses of the next stages.
M_P
Payload Mass
The payload ratio is defined as the mass of the payload divided by the empty mass of the structure. Because of the extra cost involved in staging rockets, given the choice, it's often more economic to use few stages with a small payload ratio rather than more stages each with a high payload ratio.
L
Payload Ratio
http://en.wikipedia.org/wiki/Thermoelectric_effect
http://www.iso.org/iso/catalogue_detail?csnumber=31897
\(\Pi_{ab}\)
"Peltier Coefficient" represents how much heat current is carried per unit charge through a given material. It is the heat power developed at a junction, divided by the electric current flowing from substance a to substance b.
Peltier Coefficient
Duration of one cycle of a periodic phenomenon.
belongs to SOQ-ISO
Period
Permeability
https://en.wikipedia.org/wiki/Relative_permeability
The ratio of the effective permeability of a porous phase to the absolute permeability.
Permeability Ratio
http://en.wikipedia.org/wiki/Permeance
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(\Lambda = \frac{1}{R_m}\), where \(R_m\) is reluctance.
\(\Lambda\)
"Permeance" is the inverse of reluctance. Permeance is a measure of the quantity of flux for a number of current-turns in magnetic circuit. A magnetic circuit almost acts as though the flux is "conducted", therefore permeance is larger for large cross sections of a material and smaller for longer lengths. This concept is analogous to electrical conductance in the electric circuit.
Permeance
\(A^2 \cdot s^4/kg \cdot m^3\)
\(I^2 \cdot T^4/L^3 \cdot M\)
http://dbpedia.org/resource/Permittivity
http://en.wikipedia.org/wiki/Permittivity?oldid=494094133
http://maxwells-equations.com/materials/permittivity.php
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(\epsilon = \frac{D}{E}\), where \(D\) is electric flux density and \(E\) is electric field strength.
\(\epsilon\)
"Permittivity" is a physical quantity that describes how an electric field affects, and is affected by a dielectric medium, and is determined by the ability of a material to polarize in response to the field, and thereby reduce the total electric field inside the material. Permittivity is often a scalar valued quantity, however in the general case it is tensor-valued.
Permittivity
The phase coefficient is the amount of phase shift that occurs as the wave travels one meter. Increasing the loss of the material, via the manipulation of the material's conductivity, will decrease the wavelength (increase \(\beta\)) and increase the attenuation coefficient (increase \(\alpha\)).
http://en.wikipedia.org/wiki/Attenuation_coefficient
If \(F(x) = Ae^{-\alpha x} \cos{[\beta (x - x_0)]}\), then \(\alpha\) is the attenuation coefficient and \(\beta\) is the phase coefficient.
\(\beta\)
belongs to SOQ-ISO
Phase coefficient
"Phase Difference} is the difference, expressed in electrical degrees or time, between two waves having the same frequency and referenced to the same point in time. Two oscillators that have the same frequency and different phases have a phase difference, and the oscillators are said to be out of phase with each other. The amount by which such oscillators are out of step with each other can be expressed in degrees from \SI{0}{\degree} to \SI{360}{\degree}, or in radians from 0 to \num{2\pi". If the phase difference is 180 degrees (\(\pi\) radians), then the two oscillators are said to be in antiphase.
\(phase-difference\)
http://en.wikipedia.org/wiki/Phase_(waves)#Phase_difference
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=103-07-06
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
http://www.iso.org/iso/catalogue_detail?csnumber=43012
\(\varphi = \varphi_u - \varphi_i\), where \(\varphi_u\) is the initial phase of the voltage and \(\varphi_i\) is the initial phase of the electric current.
\(\varphi\)
Phase Difference
http://en.wikipedia.org/wiki/Speed_of_sound
\(c = \frac{\omega}{k} = \lambda f\), where \(\omega\) is the angular frequency, \(k\) is angular wavenumber, \(\lambda\) is the wavelength, and \(f\) is the frequency.
In a dispersive medium sound speed is a function of sound frequency, through the dispersion relation. The spatial and temporal distribution of a propagating disturbance will continually change. Each frequency component propagates at its own Phase Velocity of Sound.
c
belongs to SOQ-ISO
Phase speed of sound
http://en.wikipedia.org/wiki/Thermal_conductivity
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Phonon Mean Free Path" is the mean free path of phonons.
l_{ph}
Phonon Mean Free Path
"Photo Threshold of Awareness Function" is the ability of the human eye to detect a light that results in a \(1^o\) radial angle at the eye with a given duration (temporal summation).
http://www.iso.org/iso/catalogue_detail?csnumber=43012
Photo Threshold of Awareness Function
A measure of flux of photons per solid angle
https://en.wikipedia.org/wiki/Photon_counting
Photon Intensity
A measure of flux of photons per surface area per solid angle
https://en.wikipedia.org/wiki/Photon_counting
Photon Radiance
https://www.dormgrow.com/par/
Photosynthetic Photon Flux (PPF) is a measurement of the total number of photons emitted by a light source each second within the PAR wavelength range and is measured in μmol/s. Lighting manufacturers may specify their grow light products in terms of PPF. It can be considered as analogous to measuring the luminous flux (lumens) of visible light which would typically require the use of an integrating sphere or a goniometer system with spectroradiometer sensor.
Photosynthetic Photon Flux
PPF
https://www.gigahertz-optik.com/en-us/service-and-support/knowledge-base/measurement-of-par/
Photosynthetically Active Radiation are the wavelengths of light within the visible range of 400 to 700 nanometers (nm) that are critical for photosynthesis. PPFD measures the amount of PAR light (photons) that arrive at the plant’s surface each second. The PPFD is measured at various distances with a Full-spectrum Quantum Sensor, also known as a PAR meter. Natural sunlight has a PAR value of 900-1500μMol/m2/s when the sun is directly overhead. For a grow light to be effective, it should have PAR values of 500-1500 μMol/m2/s.
Photosynthetic Photon Flux Density
PPFD
The \(\textit{Planck function}\) is used to compute the radiance emitted from objects that radiate like a perfect "Black Body". The inverse of the \(\textit{Planck Function}\) is used to find the \(\textit{Brightness Temperature}\) of an object. The precise formula for the Planck Function depends on whether the radiance is determined on a \(\textit{per unit wavelength}\) or a \(\textit{per unit frequency}\). In the ISO System of Quantities, \(\textit{Planck Function}\) is defined by the formula: \(Y = -G/T\), where \(G\) is Gibbs Energy and \(T\) is thermodynamic temperature.
\(B_{\nu}(T)\)
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19680008986_1968008986.pdf
http://pds-atmospheres.nmsu.edu/education_and_outreach/encyclopedia/planck_function.htm
http://www.star.nesdis.noaa.gov/smcd/spb/calibration/planck.html
http://www.iso.org/iso/catalogue_detail?csnumber=31890
The Planck function, \(B_{\tilde{\nu}}(T)\), is given by:
\(B_{\nu}(T) = \frac{2h c^2\tilde{\nu}^3}{e^{hc / k \tilde{\nu} T}-1}\)
where, \(\tilde{\nu}\) is wavelength, \(h\) is Planck's Constant, \(k\) is Boltzman's Constant, \(c\) is the speed of light in a vacuum, \(T\) is thermodynamic temperature.
Planck Function
The inclination to each other of two intersecting lines, measured by the arc of a circle intercepted between the two lines forming the angle, the center of the circle being the point of intersection. An acute angle is less than \(90^\circ\), a right angle \(90^\circ\); an obtuse angle, more than \(90^\circ\) but less than \(180^\circ\); a straight angle, \(180^\circ\); a reflex angle, more than \(180^\circ\) but less than \(360^\circ\); a perigon, \(360^\circ\). Any angle not a multiple of \(90^\circ\) is an oblique angle. If the sum of two angles is \(90^\circ\), they are complementary angles; if \(180^\circ\), supplementary angles; if \(360^\circ\), explementary angles.
http://dbpedia.org/resource/Plane_angle
http://www.thefreedictionary.com/plane+angle
An angle formed by two straight lines (in the same plane) angle - the space between two lines or planes that intersect; the inclination of one line to another; measured in degrees or radians
Plane Angle
http://en.wikipedia.org/wiki/Poisson%27s_ratio
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(\mu = \frac{\Delta \delta}{\Delta l}\), where \(\Delta \delta\) is the lateral contraction and \(\Delta l\) is the elongation.
\(\mu\)
The Poisson Ratio is the negative ratio of transverse to axial strain. In fact, when a sample object is stretched (or squeezed), to an extension (or contraction) in the direction of the applied load, it corresponds a contraction (or extension) in a direction perpendicular to the applied load. The ratio between these two quantities is the Poisson's ratio.
Poisson Ratio
The polar moment of inertia is a quantity used to predict an object's ability to resist torsion, in objects (or segments of objects) with an invariant circular cross-section and no significant warping or out-of-plane deformation. It is used to calculate the angular displacement of an object subjected to a torque. It is analogous to the area moment of inertia, which characterizes an object's ability to resist bending.
J_{zz}
http://en.wikipedia.org/wiki/Second_moment_of_area
Polar moment of inertia
"Polarizability" is the relative tendency of a charge distribution, like the electron cloud of an atom or molecule, to be distorted from its normal shape by an external electric field, which may be caused by the presence of a nearby ion or dipole. The electronic polarizability \(\alpha\) is defined as the ratio of the induced dipole moment of an atom to the electric field that produces this dipole moment. Polarizability is often a scalar valued quantity, however in the general case it is tensor-valued.
\(A^2 \cdot s^4/kg\)
\(I^2 \cdot T^4/M\)
http://dbpedia.org/resource/Polarizability
\(\alpha\)
Polarizability
The Polarization Field is the vector field that expresses the density of permanent or induced electric dipole moments in a dielectric material. The polarization vector P is defined as the ratio of electric dipole moment per unit volume.
P
Polarization Field
http://en.wikipedia.org/wiki/Position_(vector)
http://www.iso.org/iso/catalogue_detail?csnumber=43012
\(r = \overrightarrow{OP}\), where \(O\) and \(P\) are two points in space.
A "Position Vector", also known as location vector or radius vector, is a Euclidean vector which represents the position of a point P in space in relation to an arbitrary reference origin O.
r
Position Vector
http://dbpedia.org/resource/Potential_energy
http://en.wikipedia.org/wiki/Potential_energy
\(V = -\int F \cdot dr\), where \(F\) is a conservative force and \(R\) is a position vector.
http://www.iso.org/iso/catalogue_detail?csnumber=31889
Energy possessed by a body by virtue of its position in a gravity field in contrast with kinetic energy, that possessed by virtue of its motion.
PE or U
http://en.wikipedia.org/wiki/Potential_energy
Potential Energy
Power is the rate at which work is performed or energy is transmitted, or the amount of energy required or expended for a given unit of time. As a rate of change of work done or the energy of a subsystem, power is: \(P = W/t\), where \(P\) is power, \(W\) is work and {t} is time.
\(L^2 \cdot M/T^3\)
\(kg \cdot m^2/s^3\)
http://dbpedia.org/resource/Power
http://en.wikipedia.org/wiki/Power
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(P = F \cdot v\), where \(F\) is force and \(v\) is velocity.
P
p
http://en.wikipedia.org/wiki/Power_%28physics%29
Power
\(L^4 \cdot M/T^3\)
\(kg \cdot m^4/s^3\)
Power Area
\(L^4 \cdot M/T^3 \cdot U\)
\(kg \cdot m^4/s^3\)
Power Area per Solid Angle
"Power Factor", under periodic conditions, is the ratio of the absolute value of the active power \(P\) to the apparent power \(S\).
\(power-factor\)
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=131-11-46
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(\lambda = \left | P \right | / \left | S \right |\), where \(P\) is active power and \(S\) is apparent power.
\(\lambda\)
Power Factor
\(M/T^3\)
\(kg/s^3\)
http://www.physicsforums.com/library.php?do=view_item&itemid=406
Power Per Area
Power per Area Angle
\(M/\Theta^4 \cdot T^3\)
\(kg/K^4 \cdot s^3\)
Power per area quartic temperature
\(L^2 \cdot M/I \cdot T^4\)
\(kg \cdot m^2/A \cdot s^4\)
"Power Per Electric Charge" is the amount of energy generated by a unit of electric charge.
Power Per Electric Charge
\(poynting-vector\)
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=121-11-66
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(\mathbf{S} = \mathbf{E} \times \mathbf{H} \), where \(\mathbf{E}\) is electric field strength and \mathbf{H} is magnetic field strength.
\(\mathbf{S} \)
"Poynting Vector} is the vector product of the electric field strength \mathbf{E} and the magnetic field strength \mathbf{H" of the electromagnetic field at a given point. The flux of the Poynting vector through a closed surface is equal to the electromagnetic power passing through this surface. For a periodic electromagnetic field, the time average of the Poynting vector is a vector of which, with certain reservations, the direction may be considered as being the direction of propagation of electromagnetic energy and the magnitude considered as being the average electromagnetic power flux density.
Poynting Vector
http://dbpedia.org/resource/Pressure
http://en.wikipedia.org/wiki/Pressure
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(p = \frac{dF}{dA}\), where \(dF\) is the force component perpendicular to the surface element of area \(dA\).
Pressure is an effect which occurs when a force is applied on a surface. Pressure is the amount of force acting on a unit area. Pressure is distinct from stress, as the former is the ratio of the component of force normal to a surface to the surface area. Stress is a tensor that relates the vector force to the vector area.
Pressure
\(\alpha\)
Pressure Burning Rate Constant
\(\beta\)
Pressure Burning Rate Index
\(pres-coef\)
http://www.iso.org/iso/catalogue_detail?csnumber=31890
\(\beta = \left (\frac{\partial p}{\partial T} \right )_V\), where \(p\) is \(pressure\), \(T\) is thermodynamic temperature and \(V\) is volume.
\(\beta\)
Pressure Coefficient
Pressure Percentage
Pressure Ratio
https://en.wikipedia.org/wiki/Prevalence
In epidemiology, prevalence is the proportion of a particular population found to be affected by a medical condition (typically a disease or a risk factor such as smoking or seatbelt use) at a specific time. (Wikipedia)
Prevalence
The "Principal Quantum Number" describes the electron shell, or energy level, of an atom. The value of \(n\) ranges from 1 to the shell containing the outermost electron of that atom.
http://en.wikipedia.org/wiki/Quantum_number
http://www.iso.org/iso/catalogue_detail?csnumber=31894
n
Principal Quantum Number
The propagation constant, symbol \(\gamma\), for a given system is defined by the ratio of the amplitude at the source of the wave to the amplitude at some distance x.
http://en.wikipedia.org/wiki/Propagation_constant
\(\gamma = \alpha + j\beta\), where \(\alpha\) is the attenuation coefficient and \(\beta\) is the phase coefficient.
\(\gamma\)
belongs to SOQ-ISO
Propagation coefficient
Propellant Burn Rate
M_f
Propellant Mass
Propellant Mean Bulk Temperature
PMBT
Propellant Temperature
"Quality Factor", of a resonant circuit, is a measure of the "goodness" or quality of a resonant circuit. A higher value for this figure of merit correspondes to a more narrow bandwith, which is desirable in many applications. More formally, \(Q\) is the ratio of power stored to power dissipated in the circuit reactance and resistance, respectively
http://en.sourcetronic.com/electrical-measurement-glossary/quality-factor.html
http://www.allaboutcircuits.com/vol_2/chpt_6/6.html
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
If \(\underline{Z} = R + jX\), then \(Q = \left | X \right |/R\), where \(\underline{Z}\) is impedance, \(R\) is resistance, and \(X\) is reactance.
Q
Resolve Quality Facor - electronics and also doses
Quality Factor
http://en.wikipedia.org/wiki/Quantum_number
http://www.iso.org/iso/catalogue_detail?csnumber=31894
The "Quantum Number" describes values of conserved quantities in the dynamics of the quantum system. Perhaps the most peculiar aspect of quantum mechanics is the quantization of observable quantities, since quantum numbers are discrete sets of integers or half-integers.
n
Quantum Number
\(I^4 \cdot T^{10}/L^2 \cdot M^3\)
Quartic Electric Dipole Moment per Cubic Energy
A quantity of mass held by Program/project management to mitigate the risk of over-predicted performance estimates, under predicted mass estimates, and future operational and mission specific requirements (program mass reserve, manager's mass reserve, launch window reserve, performance reserve, etc.).
M_{E}
http://eaton.math.rpi.edu/CSUMS/Papers/EcoEnergy/koojimanconserve.pdf
Reserve Mass
https://www.analog.com/en/technical-articles/measurement-control-rf-power-parti.html
Radio-Frequency Power. Power level of electromagnetic waves alternating at the frequency of radio waves (up to 10^10 Hz).
RF-Power Level
In classical geometry, the "Radial Distance" is a coordinate in polar coordinate systems (r, \(\theta\)). Basically the radial distance is the scalar Euclidean distance between a point and the origin of the system of coordinates.
http://en.wikipedia.org/wiki/Radial_distance_(geometry)
http://www.iso.org/iso/catalogue_detail?csnumber=43012
\(d = \sqrt{r_1^2 + r_2^2 -2r_1r_2\cos{(\theta_1 - \theta_2)}}\), where \(P_1\) and \(P_2\) are two points with polar coordinates \((r_1, \theta_1)\) and \((r_2, \theta_2)\), respectively, and \(d\) is the distance.
\(r_Q, \rho\)
Radial Distance
\(M/T^3 \cdot U\)
\(kg/s^3\)
\(L = \frac{dI}{dA}\frac{1}{cos\alpha}\), where \(dI\) is the radiant intensity emitted from an element of the surface area \(dA\), and angle \(\alpha\) is the angle between the normal to the surface and the given direction.
"Radiance" is a radiometric measure that describes the amount of light that passes through or is emitted from a particular area, and falls within a given solid angle in a specified direction.
L
Radiance
\(\beta = \frac{L_n}{L_d}\), where \(L_n\) is the radiance of a surface element in a given direction and \(L_d\) is the radiance of the perfect reflecting or transmitting diffuser identically irradiated and viewed. Reflectance factor is equivalent to radiance factor or luminance factor (when the cone angle is infinitely small, and is equivalent to reflectance when the cone angle is \(2π sr\).
\(\beta\)
Radiance Factor is the ratio of the radiance of the surface element in the given direction to that of a perfect reflecting or transmitting diffuser identically irradiated unit.
Radiance Factor
\(M = \frac{d\Phi}{dA}\), where \(d\Phi\) is the radiant flux leaving the element of the surface area \(dA\).
Irradiance and Radiant Emittance are radiometry terms for the power per unit area of electromagnetic radiation at a surface. "Irradiance" is used when the electromagnetic radiation is incident on the surface. "Radiant emmitance" (or "radiant exitance") is used when the radiation is emerging from the surface.
Radiant Emmitance
M-L2-PER-T2
http://en.wikipedia.org/wiki/Radiant_energy
\(Q_e\)
http://www.iso.org/iso/catalogue_detail?csnumber=31895
In radiometry,"Radiant Energy} is the energy of electromagnetic waves. The quantity of radiant energy may be calculated by integrating radiant flux (or power) with respect to time. In nuclear physics, \textit{Radiant Energy" is energy, excluding rest energy, of the particles that are emitted, transferred, or received.
Q_e
R
Radiant Energy
http://www.iso.org/iso/catalogue_detail?csnumber=31892
\(w\), \(\rho = \frac{dQ}{dV}\), where \(dQ\) is the radiant energy in an elementary three-dimensional domain, and \(dV\) is the volume.
\(w, \rho\)
"Radiant Energy Density", or radiant power, is the radiant energy per unit volume.
Radiant Energy Density
J-PER-CM2
\(H = \int_{0}^{\Delta t}{E}{dt}\), where \(E\) is the irradiance acting during the time interval with duration \(\Delta t\).
Radiant exposure is a measure of the total radiant energy incident on a surface per unit area; equal to the integral over time of the radiant flux density. Also known as exposure.
H_e
Radiant Exposure
\(H_0 = \int_{0}^{\Delta t}{E_0}{dt}\), where \(E_0\) is the spherical radiance acting during time interval with duration \(\Delta t\).
Radiant fluence rate, or spherical irradiance, is equal to the total radiant flux incident on a small sphere divided by the area of the diametrical cross-section of the sphere.
H_e,0
Radiant Fluence
M-PER-T3
\(E_0 = \int{L}{d\Omega}\), where \(d\Omega\) is the solid angle of each elementary beam passing through the given point and \(L\) its radiance at that point in the direction of the beam.
Radiant fluence rate, or spherical irradiance, is equal to the total radiant flux incident on a small sphere divided by the area of the diametrical cross-section of the sphere.
E_e,0
Radiant Fluence Rate
\(\Phi = \frac{dQ}{dt}\), where \(dQ\) is the radiant energy emitted, transferred, or received during a time interval of the duration \(dt\).
\(\phi\)
Radiant Flux, or radiant power, is the measure of the total power of electromagnetic radiation (including infrared, ultraviolet, and visible light). The power may be the total emitted from a source, or the total landing on a particular surface.
Radiant Flux
\(L^2 \cdot M/T^3 \cdot U\)
\(kg \cdot m^2/s^3\)
\(I = \frac{d\Phi}{d\Omega}\), where \(d\Phi\) is the radiant flux leaving the source in an elementary cone containing the given direction with the solid angle \(d\Omega\).
Radiant Intensity is a measure of the intensity of electromagnetic radiation. It is defined as power per unit solid angle.
I
Radiant Intensity
"Radiative Heat Transfer" is proportional to \((T_1^4 - T_2^4)\) and area of the surface, where \(T_1\) and \(T_2\) are thermodynamic temperatures of two black surfaces, for non totally black surfaces an additional factor less than 1 is needed.
http://www.iso.org/iso/catalogue_detail?csnumber=43012
\(\Phi_r\)
Radiative Heat Transfer
Radiosity is the total emitted and reflected radiation leaving a surface.
Radiosity
http://dbpedia.org/resource/Radius
http://en.wikipedia.org/wiki/Radius
http://www.iso.org/iso/catalogue_detail?csnumber=43012
\(r = \frac{d}{2}\), where \(d\) is the circle diameter.
In classical geometry, the "Radius" of a circle or sphere is any line segment from its center to its perimeter the radius of a circle or sphere is the length of any such segment.
r
Radius
http://en.wikipedia.org/wiki/Radius_of_curvature_(mathematics)
http://www.iso.org/iso/catalogue_detail?csnumber=43012
\(\rho\)
In geometry, the "Radius of Curvature", R, of a curve at a point is a measure of the radius of the circular arc which best approximates the curve at that point.
Radius of Curvature
The specific heat ratio of a gas is the ratio of the specific heat at constant pressure, \(c_p\), to the specific heat at constant volume, \(c_V\). It is sometimes referred to as the "adiabatic index} or the \textit{heat capacity ratio} or the \textit{isentropic expansion factor} or the \textit{adiabatic exponent} or the \textit{isentropic exponent".
http://en.citizendium.org/wiki/Specific_heat_ratio
http://www.iso.org/iso/catalogue_detail?csnumber=31890
\(\gamma = c_p / c_V\), where \(c\) is the specific heat of a gas, \(c_p\) is specific heat capacity at constant pressure, \(c_V\) is specific heat capacity at constant volume.
\(\gamma\)
\(\varkappa\)
Ratio of Specific Heat Capacities
http://dbpedia.org/resource/Electrical_reactance
http://en.wikipedia.org/wiki/Electrical_reactance?oldid=494180019
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=131-12-46
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(X = im \underline{Z}\), where \(\underline{Z}\) is impedance and \(im\) denotes the imaginary part.
"Reactance" is the opposition of a circuit element to a change of electric current or voltage, due to that element's inductance or capacitance. A built-up electric field resists the change of voltage on the element, while a magnetic field resists the change of current. The notion of reactance is similar to electrical resistance, but they differ in several respects. Capacitance and inductance are inherent properties of an element, just like resistance.
X
Reactance
http://en.wikipedia.org/wiki/Nuclear_reaction
http://www.iso.org/iso/catalogue_detail?csnumber=31895
"Reaction Energy" in a nuclear reaction, is the sum of the kinetic energies and photon energies of the reaction products minus the sum of the kinetic and photon energies of the reactants.
Q
Reaction Energy
"Reactive Power}, for a linear two-terminal element or two-terminal circuit, under sinusoidal conditions, is the quantity equal to the product of the apparent power \(S\) and the sine of the displacement angle \(\psi\). The absolute value of the reactive power is equal to the non-active power. The ISO (and SI) unit for reactive power is the voltampere. The special name \(\textit{var}\) and symbol \(\textit{var}\) are given in IEC 60027 1.
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=131-11-44
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(Q = lm \underline{S}\), where \(\underline{S}\) is complex power. Alternatively expressed as: \(Q = S \cdot \sin \psi\), where \(\psi\) is the displacement angle.
Q
Reactive Power
http://en.wikipedia.org/wiki/Nuclear_chain_reaction
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(\rho = \frac{k_{eff} - 1}{k_{eff}}\), where \(k_{eff}\) is the effective multiplication factor.
\(\rho\)
"Reactivity" characterizes the deflection of reactor from the critical state.
Reactivity
http://www.euronuclear.org/info/encyclopedia/r/reactor-time-constant.htm
http://www.iso.org/iso/catalogue_detail?csnumber=31895
The "Reactor Time Constant", also called the reactor period, is the time during which the neutron flux density in a reactor changes by the factor e = 2.718 (e: basis of natural logarithms), when the neutron flux density increases or decreases exponentially.
T
Reactor Time Constant
http://encyclopedia2.thefreedictionary.com/recombination+coefficient
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(-\frac{dn^+}{dt} = -\frac{dn^-}{dt} = an^+n^-\), where \(n^+\) and \(n^-\) are the ion number densities of positive and negative ions, respectively, recombined during an infinitesimal time interval with duration \(dt\).
The "Recombination Coefficient" is the rate of recombination of positive ions with electrons or negative ions in a gas, per unit volume, divided by the product of the number of positive ions per unit volume and the number of electrons or negative ions per unit volume.
a
Recombination Coefficient
\(\rho = \frac{\Phi_t}{\Phi_m}\), where \(\Phi_t\) is the reflected radiant flux or the reflected luminous flux, and \(\Phi_m\) is the radiant flux or luminous flux of the incident radiation.
\(\rho\)
Refectance and reflectivity generally refer to the fraction of incident electromagnetic power that is reflected at an interface, while the term "reflection coefficient" is used for the fraction of electric field reflected. Reflectance is always a positive real number.
Refectance
http://en.wikipedia.org/wiki/Dissipation_factor
\(r= \frac{P_r}{P_i}\), where \(P_r\) is the reflected sound power, and \(P_i\) is the incident sound power.
Reflectance, or reflection factor for sound power, is the ratio of reflected sound power to incident sound power.
r
belongs to SOQ-ISO
Reflectance
\(R = \frac{\Phi_n}{\Phi_d}\), where \(\Phi_n\) is the radiant flux or luminous flux reflected in the directions delimited by a given cone and \(\Phi_d\) is the flux reflected in the same directions by an identically radiated diffuser of reflectance equal to 1.
Reflectance Factor is the measure of the ability of a surface to reflect light or other electromagnetic radiation, equal to the ratio of the reflected flux to the incident flux.
R
Reflectance Factor
http://en.wikipedia.org/wiki/Refractive_index
\(n = \frac{c_0}{c}\), where \(c_0\) is the speed of light in vacuum, and \(c\) is the speed of light in the medium.
"refractive index" or index of refraction n of a substance (optical medium) is a dimensionless number that describes how light, or any other radiation, propagates through that medium.
n
Refractive index
http://en.wikipedia.org/wiki/Relative_atomic_mass
http://www.iso.org/iso/catalogue_detail?csnumber=31894
"Relative Atomic Mass " is a dimensionless physical quantity, the ratio of the average mass of atoms of an element (from a given source) to 1/12 of the mass of an atom of carbon-12 (known as the unified atomic mass unit)
A_r
Relative Atomic Mass
\(\textit{Relative Humidity}\) is the ratio of the partial pressure of water vapor in an air-water mixture to the saturated vapor pressure of water at a prescribed temperature. The relative humidity of air depends not only on temperature but also on the pressure of the system of interest. \(\textit{Relative Humidity}\) is also referred to as \(\textit{Relative Partial Pressure}\). Relative partial pressure is often referred to as \(RH\) and expressed in percent.
http://en.wikipedia.org/wiki/Relative_humidity
http://www.iso.org/iso/catalogue_detail?csnumber=31890
\(\varphi = p / p_{sat}\), where \(p\) is partial pressure of vapour, \(p_{sat}\) is thermodynamic temperature and \(V\) is its partial pressure at saturation (at the same temperature). Relative partial pressure is often referred to as \(RH\) and expressed in percent. \(\textit{Relative Humidity}\) is also referred to as \(\textit{Relative Partial Pressure}\).
\(\varphi\)
Relative Humidity
RH
http://www.iso.org/iso/catalogue_detail?csnumber=31890
\(\varphi = v / v_{sat}\), where \(v\) is mass concentration of water vapour, \(v_{sat}\) is its mass concentration of water vapour at saturation (at the same temperature). For normal cases, the relative partial pressure may be assumed to be equal to relative mass concentration of vapour.
\(\varphi\)
"Relative Mass Concentration of Vapour" is one of a number of "Relative Concentration" quantities defined by ISO 8000.
Relative Mass Concentration of Vapour
http://en.wikipedia.org/wiki/Binding_energy
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(B_r = \frac{B}{m_u}\), where \(B\) is the mass defect and \(m_u\) is the unified atomic mass constant.
The "Relative Mass Defect" is the mass defect between the monoisotopic mass of an element and the mass of its A + 1 or its A + 2 isotopic cluster.
B_r
Relative Mass Defect
http://en.wikipedia.org/wiki/Relative_density
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(d = \frac{\rho}{\rho_0}\), where \(\rho\) is mass density of a substance and \(\rho_0\) is the mass density of a reference substance under conditions that should be specified for both substances.
Relative density, or specific gravity, is the ratio of the density (mass of a unit volume) of a substance to the density of a given reference material.
d
Relative Mass Density
http://en.wikipedia.org/wiki/Mass_excess
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(\Delta_r = \frac{\Delta}{m_u}\), where \(\Delta\) is the mass excess and \(m_u\) is the unified atomic mass constant.
\(\Delta_r\)
The "Relative Mass Excess" is the mass excess between the monoisotopic mass of an element and the mass of its A + 1 or its A + 2 isotopic cluster (extrapolated from relative mass defect).
Relative Mass Excess
http://www.iso.org/iso/catalogue_detail?csnumber=31890
\(\psi = x / x_{sat}\), where \(x\) is mass ratio of water vapour to dry gas, \(x_{sat}\) is its mass raio of water vapour to dry gas at saturation (at the same temperature).
\(\psi\)
"Relative Mass Ratio of Vapour" is one of a number of "Relative Concentration" quantities defined by ISO 8000.
Relative Mass Ratio of Vapour
http://en.wikipedia.org/wiki/Molecular_mass#Relative_molecular_mass
http://www.iso.org/iso/catalogue_detail?csnumber=31894
"Relative Molecular Mass " is equivalent to the numerical value of the molecular mass expressed in unified atomic mass units. The molecular mass (m) is the mass of a molecule.
M_r
Relative Molecular Mass
http://www.iso.org/iso/catalogue_detail?csnumber=31890
\(\varphi = p / p_{sat}\), where \(p\) is partial pressure of vapour, \(p_{sat}\) is thermodynamic temperature and \(V\) is its partial pressure at saturation (at the same temperature). Relative partial pressure is often referred to as \(RH\) and expressed in percent. \(\textit{Relative Partial Pressure}\) is also referred to as \(\textit{Relative Humidity}\).
\(\varphi\)
Relative Partial Pressure
RH
http://dbpedia.org/resource/Permittivity
\(rel-permittivity\)
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(\epsilon_r = \epsilon / \epsilon_0\), where \(\epsilon\) is permittivity and \(\epsilon_0\) is the electric constant.
\(\epsilon_r\)
"Relative Permittivity" is the ration of permittivity to the permittivity of a vacuum.
Relative Permittivity
\(rel-pres-coef\)
http://www.iso.org/iso/catalogue_detail?csnumber=31890
\(\alpha_p = \frac{1}{p}\left (\frac{\partial p}{\partial T} \right )_V\), where \(p\) is \(pressure\), \(T\) is thermodynamic temperature and \(V\) is volume.
\(\alpha_p\)
Relative Pressure Coefficient
http://en.wikipedia.org/wiki/Relaxation_(physics)
http://www.iso.org/iso/catalogue_detail?csnumber=31897
\(\tau\)
"Relaxation TIme" is a time constant for exponential decay towards equilibrium.
Relaxation TIme
http://en.wikipedia.org/wiki/Magnetic_reluctance
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(R_m = \frac{U_m}{\Phi}\), where \(U_m\) is magnetic tension, and \(\Phi\) is magnetic flux.
"Reluctance" or magnetic resistance, is a concept used in the analysis of magnetic circuits. It is analogous to resistance in an electrical circuit, but rather than dissipating electric energy it stores magnetic energy. In likeness to the way an electric field causes an electric current to follow the path of least resistance, a magnetic field causes magnetic flux to follow the path of least magnetic reluctance. It is a scalar, extensive quantity, akin to electrical resistance.
R_m
Reluctance
http://en.wikipedia.org/wiki/Residual-resistance_ratio
http://www.iso.org/iso/catalogue_detail?csnumber=31897
\(\rho_R\)
"Residual Resistivity" for metals, is the resistivity extrapolated to zero thermodynamic temperature.
Residual Resistivity
\(L^2 \cdot M/I^2 \cdot T^3\)
\(kg \cdot m^2/A^2 \cdot s^3\)
http://dbpedia.org/resource/Resistance
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=131-12-45
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(R = \frac{u}{i}\), where \(u\) is instantaneous voltage and \(i\) is instantaneous electric current.
The electrical resistance of an object is a measure of its opposition to the passage of a steady electric current.
R
Resistance
Resistance Percentage
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=121-12-04
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(\rho = \frac{1}{\sigma}\), if it exists, where \(\sigma\) is conductivity.
\(\rho\)
"Resistivity" is the inverse of the conductivity when this inverse exists.
Resistivity
http://en.wikipedia.org/wiki/Nuclear_reaction_analysis
http://www.iso.org/iso/catalogue_detail?csnumber=31895
"Resonance Energy" in a nuclear reaction, is the kinetic energy of an incident particle, in the reference frame of the target, corresponding to a resonance in a nuclear reaction.
E_r, E_{res}
Resonance Energy
http://en.wikipedia.org/wiki/Four_factor_formula
http://www.iso.org/iso/catalogue_detail?csnumber=31895
The "Resonance Escape Probability" is the fraction of fission neutrons that manage to slow down from fission to thermal energies without being absorbed. In an infinite medium, the probability that a neutron slowing down will traverse all or some specified portion of the range of resonance energies without being absorbed.
p
Resonance Escape Probability
Fraction of fission neutrons that manage to slow down from fission to thermal energies without being absorbed.
p
Resonance Escape Probability For Fission
http://dbpedia.org/resource/Respiratory_rate
http://en.wikipedia.org/wiki/Respiratory_rate
Respiratory rate (Vf, Rf or RR) is also known by respiration rate, pulmonary ventilation rate, ventilation rate, or breathing frequency is the number of breaths taken within a set amount of time, typically 60 seconds. A normal respiratory rate is termed eupnea, an increased respiratory rate is termed tachypnea and a lower than normal respiratory rate is termed bradypnea.
Vf, Rf or RR
Respiratory Rate
http://en.wikipedia.org/wiki/Invariant_mass#Rest_energy
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31895
For a particle, \(E_0 = m_0 c_0^2\), where \(m_0\) is the rest mass of that particle, and \(c_0\) is the speed of light in vacuum.
http://www.iso.org/iso/catalogue_detail?csnumber=31895
"Rest Energy" is the energy equivalent of the rest mass of a body, equal to the rest mass multiplied by the speed of light squared.
E_0
Rest Energy
The \(\textit{Rest Mass}\), the invariant mass, intrinsic mass, proper mass, or (in the case of bound systems or objects observed in their center of momentum frame) simply mass, is a characteristic of the total energy and momentum of an object or a system of objects that is the same in all frames of reference related by Lorentz transformations. The mass of a particle type X (electron, proton or neutron) when that particle is at rest. For an electron: \(m_e = 9,109 382 15(45) 10^{-31} kg\), for a proton: \(m_p = 1,672 621 637(83) 10^{-27} kg\), for a neutron: \(m_n = 1,674 927 211(84) 10^{-27} kg\). Rest mass is often denoted \(m_0\).
http://en.wikipedia.org/wiki/Invariant_mass
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31895
http://www.iso.org/iso/catalogue_detail?csnumber=31895
m_X
Rest Mass
Proper Mass
http://en.wikipedia.org/wiki/Reverberation
Reverberation Time is the time required for reflections of a direct sound to decay by 60 dB below the level of the direct sound.
T
belongs to SOQ-ISO
Reverberation Time
http://dbpedia.org/resource/Reynolds_number
\(Re = \frac{\rho uL}{\mu} = \frac{uL}{\nu}\), where \(\rho\) is mass density, \(u\) is speed, \(L\) is length, \(\mu\) is dynamic viscosity, and \(\nu\) is kinematic viscosity.
http://www.iso.org/iso/catalogue_detail?csnumber=31896
The "Reynolds Number" (Re) is a dimensionless number that gives a measure of the ratio of inertial forces to viscous forces and consequently quantifies the relative importance of these two types of forces for given flow conditions.
Re
Reynolds Number
http://en.wikipedia.org/wiki/Thermionic_emission
http://www.iso.org/iso/catalogue_detail?csnumber=31897
The thermionic emission current, \(J\), for a metal is \(J = AT^2\exp{(-\frac{\Phi}{kT})}\), where \(T\) is thermodynamic temperature, \(k\) is the Boltzmann constant, and \(\Phi\) is a work function.
"Richardson Constant" is a constant used in developing thermionic emission current density for a metal.
A
Richardson Constant
Transverse force on rocket due to an atmosphere
T
Rocket Atmospheric Transverse Force
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=121-11-58
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(\mathbf{H} = -grad V_m\), where \(\mathbf{H}\) is magnetic field strength.
\(\varphi\)
"Scalar Magnetic Potential" is the scalar potential of an irrotational magnetic field strength. The negative of the gradient of the scalar magnetic potential is the irrotational magnetic field strength. The magnetic scalar potential is not unique since any constant scalar field can be added to it without changing its gradient.
V_m
Scalar Magnetic Potential
\(m^4\)
http://en.wikipedia.org/wiki/Second_moment_of_area
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(I_a = \int r^2_Q dA\), where \(r_Q\) is the radial distance from a \(Q-axis\) and \(A\) is area.
The moment of inertia, also called mass moment of inertia, rotational inertia, polar moment of inertia of mass, or the angular mass is a property of a distribution of mass in space that measures its resistance to rotational acceleration about an axis.
I
Second Axial Moment of Area
The second moment of area is a property of a physical object that can be used to predict its resistance to bending and deflection. The deflection of an object under load depends not only on the load, but also on the geometry of the object's cross-section.
J
http://en.wikipedia.org/wiki/Second_moment_of_area
Second Moment of Area
http://en.wikipedia.org/wiki/Second_moment_of_area
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(I_p = \int r^2_Q dA\), where \(r_Q\) is the radial distance from a \(Q-axis\) and \(A\) is area.
The moment of inertia, also called mass moment of inertia, rotational inertia, polar moment of inertia of mass, or the angular mass is a property of a distribution of mass in space that measures its resistance to rotational acceleration about an axis.
I
Second Polar Moment of Area
Mass ratio for the second stage of a multistage launcher.
R_2
Second Stage Mass Ratio
http://en.wikipedia.org/wiki/Section_modulus
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(Z = \frac{I_a}{(r_Q)_{max}}\), where \(I_a\) is the second axial moment of area and \((r_Q)_{max}\) is the maximum radial distance of any point in the surface considered from the \(Q-axis\) with respect to which \(I_a\) is defined.
The Section Modulus is a geometric property for a given cross-section used in the design of beams or flexural members.
Z
Section Modulus
http://en.wikipedia.org/wiki/Thermopower
http://www.iso.org/iso/catalogue_detail?csnumber=31897
\(S_{ab} = \frac{dE_{ab}}{dT}\), where \(E_{ab}\) is the thermosource voltage between substances a and b, \(T\) is the thermodynamic temperature of the hot junction.
"Seebeck Coefficient", or thermopower, or thermoelectric power of a material is a measure of the magnitude of an induced thermoelectric voltage in response to a temperature difference across that material.
S_{ab}
Seebeck Coefficient
Serum or Plasma Level
The Shear Modulus or modulus of rigidity, denoted by \(G\), or sometimes \(S\) or \(\mu\), is defined as the ratio of shear stress to the shear strain.
http://en.wikipedia.org/wiki/Shear_modulus
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(G = \frac{\tau}{\gamma}\), where \(\tau\) is the shear stress and \(\gamma\) is the shear strain.
G
Shear Modulus
http://en.wikipedia.org/wiki/Deformation_(mechanics)
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(\gamma = \frac{\Delta x}{d}\), where \(\Delta x\) is the parallel displacement between two surfaces of a layer of thickness \(d\).
\(\gamma\)
Shear Strain is the amount of deformation perpendicular to a given line rather than parallel to it.
Shear Strain
\(n m^{-2}\)
http://en.wikipedia.org/wiki/Stress_(mechanics)
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(\tau = \frac{dF_t}{dA}\), where \(dF_t\) is the tangential component of force and \(dA\) is the area of the surface element.
\(\tau\)
Shear stress occurs when the force occurs in shear, or perpendicular to the normal.
Shear Stress
http://www.iso.org/iso/catalogue_detail?csnumber=31897
\(r, \sigma\)
"Short-Range Order Parameter" is the fraction of the nearest-neighbor atom pairs in an Ising ferromagnet having magnetic moments in one direction, minus the fraction having magnetic moments in the opposite direction.
Short-Range Order Parameter
Signal Detection Threshold
http://dbpedia.org/resource/Signal_strength
In telecommunications, particularly in radio, signal strength refers to the magnitude of the electric field at a reference point that is a significant distance from the transmitting antenna. It may also be referred to as received signal level or field strength. Typically, it is expressed in voltage per length or signal power received by a reference antenna. High-powered transmissions, such as those used in broadcasting, are expressed in dB-millivolts per metre (dBmV/m).
Signal Strength
R_o
Single Stage Launcher Mass Ratio
http://www.iso.org/iso/catalogue_detail?csnumber=31895
"Slowing-Down Area" in an infinite homogenous medium, is one-sixth of the mean square distance between the neutron source and the point where a neutron reaches a given energy.
L_s^2
Slowing-Down Area
http://encyclopedia2.thefreedictionary.com/slowing-down+density
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(q = -\frac{dn}{dt}\), where \(n\) is the number density and \(dt\) is the duration.
"Slowing-Down Density" is a measure of the rate at which neutrons lose energy in a nuclear reactor through collisions; equal to the number of neutrons that fall below a given energy per unit volume per unit time.
q
Slowing-Down Density
http://nuclearpowertraining.tpub.com/h1013v2/css/h1013v2_32.htm
http://www.iso.org/iso/catalogue_detail?csnumber=31895
"Slowing-Down Length" is the average straight-line distance that a fast neutron will travel between its introduction into the slowing-downmedium (moderator) and thermalization.
L_s
Slowing-Down Length
http://dbpedia.org/resource/Solid_angle
The solid angle subtended by a surface S is defined as the surface area of a unit sphere covered by the surface S's projection onto the sphere. A solid angle is related to the surface of a sphere in the same way an ordinary angle is related to the circumference of a circle. Since the total surface area of the unit sphere is 4*pi, the measure of solid angle will always be between 0 and 4*pi.
Solid Angle
http://pveducation.org/pvcdrom/pn-junction/diffusion-length
\(L = \sqrt{D\tau}\), where \(D\) is the diffusion coefficient and \(\tau\) is lifetime.
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Solid State Diffusion Length" is the average distance traveled by a particle, such as a minority carrier in a semiconductor
L, L_n, L_p
Diffusion Length (Solid State Physics)
Sound energy density is the time-averaged sound energy in a given volume divided by that volume. The sound energy density or sound density (symbol \(E\) or \(w\)) is an adequate measure to describe the sound field at a given point as a sound energy value.
http://en.wikipedia.org/wiki/Sound_energy_density
\(E = \frac{I}{c}\), where \(I\) is the sound intensity in \(\frac{W}{m^2}\) and \(c\) is the sound speed in \(\frac{m}{s}\).
E
belongs to SOQ-ISO
Sound energy density
http://www.acoustic-glossary.co.uk/definitions-s.htm
\(E = \int_{t1}^{t2}p^2dt\), where \(t1\) and \(t2\) are the starting and ending times for the integral and \(p\) is the sound pressure.
Sound Exposure is the energy of the A-weighted sound calculated over the measurement time(s). For a given period of time, an increase of 10 dB(A) in sound pressure level corresponds to a tenfold increase in E.
E
belongs to SOQ-ISO
Sound exposure
Sound Exposure Level abbreviated as \(SEL\) and \(LAE\), is the total noise energy produced from a single noise event.
http://www.diracdelta.co.uk/science/source/s/o/sound%20exposure%20level/source.html
\(L_E = 10 \log_{10} \frac{E}{E_0} dB\), where \(E\) is sound power and the reference value is \(E_0 = 400 \mu Pa^2 s\).
L
belongs to SOQ-ISO
Sound exposure level
w/m2
http://en.wikipedia.org/wiki/Sound_intensity
\(I = pv\), where \(p\) is the sound pressure and \(v\) is sound particle velocity.
Sound intensity or acoustic intensity (\(I\)) is defined as the sound power \(P_a\) per unit area \(A\). The usual context is the noise measurement of sound intensity in the air at a listener's location as a sound energy quantity.
I
belongs to SOQ-ISO
Sound intensity
In a compressible sound transmission medium - mainly air - air particles get an accelerated motion: the particle acceleration or sound acceleration with the symbol a in \(m/s2\). In acoustics or physics, acceleration (symbol: \(a\)) is defined as the rate of change (or time derivative) of velocity.
http://en.wikipedia.org/wiki/Particle_acceleration
\(a = \frac{\partial v}{\partial t}\), where \(v\) is sound particle velocity and \(t\) is time.
a
belongs to SOQ-ISO
Sound particle acceleration
l
http://en.wikipedia.org/wiki/Particle_displacement
Sound Particle Displacement is the nstantaneous displacement of a particle in a medium from what would be its position in the absence of sound waves.
ξ
belongs to SOQ-ISO
Sound Particle Displacement
http://en.wikipedia.org/wiki/Particle_velocity
\(v = \frac{\partial\delta }{\partial t}\), where \(\delta\) is sound particle displacement and \(t\) is time.
Sound Particle velocity is the velocity v of a particle (real or imagined) in a medium as it transmits a wave. In many cases this is a longitudinal wave of pressure as with sound, but it can also be a transverse wave as with the vibration of a taut string. When applied to a sound wave through a medium of a fluid like air, particle velocity would be the physical speed of a parcel of fluid as it moves back and forth in the direction the sound wave is travelling as it passes.
v
belongs to SOQ-ISO
Sound particle velocity
Sound power or acoustic power \(P_a\) is a measure of sonic energy \(E\) per time \(t\) unit. It is measured in watts and can be computed as sound intensity (\(I\)) times area (\(A\)).
http://en.wikipedia.org/wiki/Sound_power
\(P_a = IA\), where \(I\) is the sound intensity in \(\frac{W}{m^2}\) and \(A\) is the area in \(m^2\).
P
belongs to SOQ-ISO
Sound power
Sound Power Level abbreviated as \(SWL\) expresses sound power more practically as a relation to the threshold of hearing - 10-12 W - in a logarithmic scale.
http://en.wikipedia.org/wiki/Sound_power#Sound_power_level
\(L_W = 10 \log_{10} \frac{P}{P_0} dB\), where \(P\) is sound power and the reference value is \(P_0 =1pW\).
L
belongs to SOQ-ISO
Sound power level
p
http://en.wikipedia.org/wiki/Static_pressure
Sound Pressure is the difference between instantaneous total pressure and static pressure.
p
belongs to SOQ-ISO
Sound pressure
Sound pressure level (\(SPL\)) or sound level is a logarithmic measure of the effective sound pressure of a sound relative to a reference value. It is measured in decibels (dB) above a standard reference level.
http://en.wikipedia.org/wiki/Sound_pressure#Sound_pressure_level
\(L_P = 10 \log_{10} \frac{p^2}{p_0^2} dB\), where \(p\) is sound pressure and the reference value in airborne acoustics is \(p_0 = 20 \mu Pa\).
L
belongs to SOQ-ISO
Sound pressure level
http://en.wikipedia.org/wiki/Sound_reduction_index
\(R = 10 \log (\frac{1}{\tau}) dB\), where \(\tau\) is the transmission factor.
The Sound Reduction Index is used to measure the level of sound insulation provided by a structure such as a wall, window, door, or ventilator.
R
belongs to SOQ-ISO
Sound reduction index
Sound Volume Velocity is the product of particle velocity \(v\) and the surface area \(S\) through which an acoustic wave of frequency \(f\) propagates. Also, the surface integral of the normal component of the sound particle velocity over the cross-section (through which the sound propagates). It is used to calculate acoustic impedance.
http://en.wikipedia.org/wiki/Acoustic_impedance
\(q= vS\), where \(v\) is sound particle velocity and \(S\) is the surface area through which an acoustic wave of frequence \(f\) propagates.
q
belongs to SOQ-ISO
Sound volume velocity
"Source Voltage}, also referred to as \textit{Source Tension" is the voltage between the two terminals of a voltage source when there is no
electric current through the source. The name "electromotive force} with the abbreviation \textit{EMF" and the symbol \(E\) is deprecated.
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
U_s
Source Voltage
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Source Voltage Between Substances" is the source voltage between substance a and b.
E_{ab}
Source Voltage Between Substances
http://www.iso.org/iso/catalogue_detail?csnumber=43012
"Spatial Summation Function" is he ability to produce a composite signal from the signals coming into the eyes from different directions.
Spatial Summation Function
Specific Acoustic Impedance
http://en.wikipedia.org/wiki/Specific_activity
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(a = \frac{A}{m}\), where \(A\) is the activity of a sample and \(m\) is its mass.
The "Specific Activity" is the number of decays per unit time of a radioactive sample. The SI unit of radioactive activity is the becquerel (Bq), in honor of the scientist Henri Becquerel.
a
Specific Activity
\(\textbf{Specific Energy}\) is defined as the energy per unit mass. Common metric units are \(J/kg\). It is an intensive property. Contrast this with energy, which is an extensive property. There are two main types of specific energy: potential energy and specific kinetic energy. Others are the \(\textbf{gray}\) and \(\textbf{sievert}\), which are measures for the absorption of radiation. The concept of specific energy applies to a particular or theoretical way of extracting useful energy from the material considered that is usually implied by context. These intensive properties are each symbolized by using the lower case letter of the symbol for the corresponding extensive property, which is symbolized by a capital letter. For example, the extensive thermodynamic property enthalpy is symbolized by \(H\); specific enthalpy is symbolized by \(h\).
\(L^2/T^2\)
\(m^2/s^2\)
http://dbpedia.org/resource/Specific_energy
http://en.citizendium.org/wiki/Enthalpy
http://en.wikipedia.org/wiki/Specific_energy
\(e = E/m\), where \(E\) is energy and \(m\) is mass.
e
Specific Energy
http://www.answers.com/topic/energy-imparted
http://www.iso.org/iso/catalogue_detail?csnumber=31895
For ionizing radiation, \(z = \frac{\varepsilon}{m}\), where \(\varepsilon\) is the energy imparted to irradiated matter and \(m\) is the mass of that matter.
The "Specific Energy Imparted", is the energy imparted to an element of irradiated matter divided by the mass, dm, of that element.
z
Specific Energy Imparted
\(\textit{Specific Enthalpy}\) is enthalpy per mass of substance involved. Specific enthalpy is denoted by a lower case h, with dimension of energy per mass (SI unit: joule/kg). In thermodynamics, \(\textit{enthalpy}\) is the sum of the internal energy U and the product of pressure p and volume V of a system: \(H = U + pV\). The internal energy U and the work term pV have dimension of energy, in SI units this is joule; the extensive (linear in size) quantity H has the same dimension.
http://dbpedia.org/resource/Entropy
http://en.citizendium.org/wiki/Enthalpy
http://www.iso.org/iso/catalogue_detail?csnumber=31890
\(h = H/m\), where \(H\) is enthalpy and \(m\) is mass.
h
Specific Enthalpy
http://dbpedia.org/resource/Entropy
http://www.iso.org/iso/catalogue_detail?csnumber=31890
\(s = S/m\), where \(S\) is entropy and \(m\) is mass.
"Specific Entropy" is entropy per unit of mass.
s
Specific Entropy
http://en.citizendium.org/wiki/Enthalpy
http://www.iso.org/iso/catalogue_detail?csnumber=31890
\(g = G/m\), where \(G\) is Gibbs energy and \(m\) is mass.
Energy has corresponding intensive (size-independent) properties for pure materials. A corresponding intensive property is "Specific Gibbs Energy}, which is \textit{Gibbs Energy} per mass of substance involved. \textit{Specific Gibbs Energy" is denoted by a lower case g, with dimension of energy per mass (SI unit: joule/kg).
g
Specific Gibbs Energy
\(L^2/\Theta \cdot T^2\)
\(m^2/K \cdot s^2\)
http://dbpedia.org/resource/Specific_heat_capacity
http://www.taftan.com/thermodynamics/CP.HTM
"Specific Heat Capacity} of a solid or liquid is defined as the heat required to raise unit mass of substance by one degree of temperature. This is \textit{Heat Capacity} divied by \textit{Mass". Note that there are corresponding molar quantities.
c
Specific Heat Capacity
Specific heat at a constant pressure.
c_p
Specific heat capacity at constant pressure
Specific heat per constant volume.
c_v
Specific heat capacity at constant volume
http://www.iso.org/iso/catalogue_detail?csnumber=31890
Specific heat per constant volume.
c_{sat}
Specific Heat Capacity at Saturation
\(L^3/\Theta \cdot M\)
\(m^3/K \cdot kg\)
Specific heat at a constant pressure.
Specific Heat Pressure
\(/K \cdot m \cdot s^2\)
\(/\Theta \cdot L \cdot T^2\)
Specific heat per constant volume.
Specific Heat Volume
The ratio of specific heats, for the exhaust gases adiabatic gas constant, is the relative amount of compression/expansion energy that goes into temperature \(T\) versus pressure \(P\) can be characterized by the heat capacity ratio: \(\gamma\frac{C_P}{C_V}\), where \(C_P\) is the specific heat (also called heat capacity) at constant pressure, while \(C_V\) is the specific heat at constant volume.
\(\gamma\)
Specific Heats Ratio
Energy has corresponding intensive (size-independent) properties for pure materials. A corresponding intensive property is \(\textit{Specific Helmholtz Energy}\), which is \(\textit{Helmholz Energy}\) per mass of substance involved.\( \textit{Specific Helmholz Energy}\) is denoted by a lower case u, with dimension of energy per mass (SI unit: joule/kg).
http://en.citizendium.org/wiki/Enthalpy
http://www.iso.org/iso/catalogue_detail?csnumber=31890
\(a = A/m\), where \(A\) is Helmholtz energy and \(m\) is mass.
a
Specific Helmholtz Energy
The impulse produced by a rocket divided by the mass \(mp\) of propellant consumed. Specific impulse \({I_{sp}}\) is a widely used measure of performance for chemical, nuclear, and electric rockets. It is usually given in seconds for both U.S. Customary and International System (SI) units. The impulse produced by a rocket is the thrust force \(F\) times its duration \(t\) in seconds. \(I_{sp}\) is the thrust per unit mass flowrate, but with \(g_o\), is the thrust per weight flowrate. The specific impulse is given by the equation: \(I_{sp} = \frac{F}{\dot{m}g_o}\).
http://www.grc.nasa.gov/WWW/K-12/airplane/specimp.html
Specific Impulse
Specific Impulse by Mass
Specific Impulse by Weight
http://en.citizendium.org/wiki/Enthalpy
http://www.iso.org/iso/catalogue_detail?csnumber=31890
\(u = U/m\), where \(U\) is thermodynamic energy and \(m\) is mass.
Energy has corresponding intensive (size-independent) properties for pure materials. A corresponding intensive property is specific internal energy, which is energy per mass of substance involved. Specific internal energy is denoted by a lower case u, with dimension of energy per mass (SI unit: joule/kg).
u
Specific Internal Energy
http://goldbook.iupac.org/O04313.html
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(\alpha_m = \alpha \frac{A}{m}\), where \(\alpha\) is the angle of optical rotation, and \(m\) is the mass of the optically active component in the path of a linearly polarized light beam of cross sectional area \(A\).
\(\alpha_m\)
The "Specific Optical Rotatory Power" Angle of optical rotation divided by the optical path length through the medium and by the mass concentration of the substance giving the specific optical rotatory power.
Specific Optical Rotatory Power
http://dbpedia.org/resource/Specific_thrust
Q-160-100
http://en.wikipedia.org/wiki/Specific_thrust
Specific impulse (usually abbreviated Isp) is a way to describe the efficiency of rocket and jet engines. It represents the force with respect to the amount of propellant used per unit time.[1] If the "amount" of propellant is given in terms of mass (such as kilograms), then specific impulse has units of velocity. If it is given in terms of Earth-weight (such as kiloponds), then specific impulse has units of time. The conversion constant between the two versions of specific impulse is g. The higher the specific impulse, the lower the propellant flow rate required for a given thrust, and in the case of a rocket the less propellant is needed for a given delta-v per the Tsiolkovsky rocket equation.
Specific thrust
"Specific Volume" (\(\nu\)) is the volume occupied by a unit of mass of a material. It is equal to the inverse of density.
\(L^3/M\)
http://en.wikipedia.org/wiki/Specific_volume
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(sv = \frac{1}{\rho}\), where \(\rho\) is mass density.
Specific Volume
"Spectral Angular Cross-section" is the cross-section for ejecting or scattering a particle into an elementary cone with energy \(E\) in an energy interval, divided by the solid angle \(d\Omega\) of that cone and the range \(dE\) of that interval.
http://en.wikipedia.org/wiki/Cross_section_(physics)
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(\sigma = \int \int \sigma_{\Omega,E} d\Omega dE\)
\(\sigma_{\Omega, E}\)
Spectral Angular Cross-section
"Spectral Cross-section" is the cross-section for a process in which the energy of the ejected or scattered particle is in an interval of energy, divided by the range \(dE\) of this interval.
http://en.wikipedia.org/wiki/Cross_section_(physics)
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(\sigma = \int \sigma_E dE\)
\(\sigma_E\)
Spectral Cross-section
\(V(\lambda) = \frac{\Phi_\lambda(\lambda_m)}{\Phi_\lambda(\lambda)}\), where \(\Phi_\lambda(\lambda_m)\) is the spectral radiant flux at wavelength \(\lambda_m\) and \(\Phi_\lambda(\lambda)\) is the spectral radiant flux at wavelength \(\lambda\), such that both radiations produce equal luminous sensations under specified photometric conditions and \(\lambda_m\) is chosen so that the maximum value of this ratio is equal to 1.
The Spectral Luminous Efficiency is a measure of how well a light source produces visible light. It is the ratio of luminous flux to power. A common choice is to choose units such that the maximum possible efficacy, 683 lm/W, corresponds to an efficiency of 100%.
V
Spectral Luminous Efficiency
\(M-PER-L2-T2\)
"Spectral Radiant Energy Density" is the spectral concentration of radiant energy density (in terms of wavelength), or the spectral radiant energy density (in terms of wave length).
Spectral Radiant Energy Density
http://dbpedia.org/resource/Speed
Speed is the magnitude of velocity.
Speed
The quantity kind \(\textbf{Speed of Light}\) is the speed of electomagnetic waves in a given medium.
http://dbpedia.org/resource/Speed_of_light
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=113-01-34
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
Speed of Light
http://dbpedia.org/resource/Speed_of_sound
http://en.wikipedia.org/wiki/Speed_of_sound
\(c = \sqrt{\frac{K}{\rho}}\), where \(K\) is the coefficient of stiffness, the bulk modulus (or the modulus of bulk elasticity for gases), and \(\rho\) is the density. Also, \(c^2 = \frac{\partial p}{\partial \rho}\), where \(p\) is the pressure and \(\rho\) is the density.
The speed of sound is the distance travelled during a unit of time by a sound wave propagating through an elastic medium.
c
belongs to SOQ-ISO
Speed of sound
Spherical illuminance is equal to quotient of the total luminous flux \(\Phi_v\) incident on a small sphere by the cross section area of that sphere.
\(E_v,0 = \int_{4\pi sr}{L_v}{d\Omega}\), where \(d\Omega\) is the solid angle of each elementary beam passing through the given point and \(L_v\) is its luminance at that point in the direction of the beam.
Illuminance
http://en.wikipedia.org/wiki/Spin_(physics)
http://www.iso.org/iso/catalogue_detail?csnumber=31895
In quantum mechanics and particle physics "Spin" is an intrinsic form of angular momentum carried by elementary particles, composite particles (hadrons), and atomic nuclei.
s
Spin
http://en.wikipedia.org/wiki/Quantum_number
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(s^2 = \hbar^2 s(s + 1)\), where \(s\) is the spin quantum number and \(\hbar\) is the Planck constant.
The "Spin Quantum Number" describes the spin (intrinsic angular momentum) of the electron within that orbital, and gives the projection of the spin angular momentum S along the specified axis
s
Spin Quantum Number
\(L^4 \cdot M^2/T^4\)
\(kg^2 \cdot m^4/s^4\)
Square Energy
M_F
Stage Propellant Mass
M_S
Stage Structure Mass
The "Standard Absolute Activity" is proportional to the absoulte activity of the pure substance \(B\) at the same temperature and pressure multiplied by the standard pressure.
http://en.wikipedia.org/wiki/Activity_coefficient
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(\lambda_B^\Theta = \lambda_B^*(p^\Theta)\), where \(\lambda_B^\Theta\) the absolute activity of the pure substance \(B\) at the same temperature and pressure, and \(p^\Theta\) is standard pressure.
\(\lambda_B^\Theta\)
Standard Absolute Activity
\(j-mol^{-1}\)
http://en.wikipedia.org/wiki/Chemical_potential
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(\mu_B^\Theta\)
"Standard Chemical Potential" is the value of the chemical potential at standard conditions
Standard Chemical Potential
In celestial mechanics the standard gravitational parameter of a celestial body is the product of the gravitational constant G and the mass M of the body. Expressed as \(\mu = G \cdot M\). The SI units of the standard gravitational parameter are \(m^{3}s^{-2}\).
\(L^3/T^2\)
\(m^3/s^2\)
http://dbpedia.org/resource/Standard_gravitational_parameter
http://en.wikipedia.org/wiki/Standard_gravitational_parameter
\(\mu\)
Standard Gravitational Parameter
http://dbpedia.org/resource/Friction
http://en.wikipedia.org/wiki/Friction
http://www.iso.org/iso/catalogue_detail?csnumber=31889
Static friction is friction between two or more solid objects that are not moving relative to each other. For example, static friction can prevent an object from sliding down a sloped surface.
Static Friction
http://dbpedia.org/resource/Friction
http://en.wikipedia.org/wiki/Friction
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(\mu = \frac{F_max}{N}\), where \(F_max\) is the maximum tangential component of the contact force and \(N\) is the normal component of the contact force between two bodies at relative rest.
\(\mu\)
Static friction is friction between two or more solid objects that are not moving relative to each other. For example, static friction can prevent an object from sliding down a sloped surface.
Static Friction Coefficient
"Static Pressure" is the pressure at a nominated point in a fluid. Every point in a steadily flowing fluid, regardless of the fluid speed at that point, has its own static pressure \(P\), dynamic pressure \(q\), and total pressure \(P_0\). The total pressure is the sum of the dynamic and static pressures, that is \(P_0 = P + q\).
p
http://en.wikipedia.org/wiki/Static_pressure
p
belongs to SOQ-ISO
Static pressure
http://en.wikipedia.org/wiki/Statistical_weight
http://www.iso.org/iso/catalogue_detail?csnumber=31894
A "Statistical Weight" is the relative probability (possibly unnormalized) of a particular feature of a state.
g
Statistical Weight
http://dbpedia.org/resource/Stochastic_process
http://en.wikipedia.org/wiki/Stochastic_process
In probability theory, a stochastic process, or sometimes random process is a collection of random variables; this is often used to represent the evolution of some random value, or system, over time. This is the probabilistic counterpart to a deterministic process (or deterministic system).
X
Stochastic Process
http://en.wikipedia.org/wiki/Stoichiometry
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(\nu_B\)
Chemical reactions, as macroscopic unit operations, consist of simply a very large number of elementary reactions, where a single molecule reacts with another molecule. As the reacting molecules (or moieties) consist of a definite set of atoms in an integer ratio, the ratio between reactants in a complete reaction is also in integer ratio. A reaction may consume more than one molecule, and the "Stoichiometric Number" counts this number, defined as positive for products (added) and negative for reactants (removed).
Stoichiometric Number
http://dbpedia.org/resource/Strain
\(\epsilon\)
In any branch of science dealing with materials and their behaviour, strain is the geometrical expression of deformation caused by the action of stress on a physical body. Strain is calculated by first assuming a change between two body states: the beginning state and the final state. Then the difference in placement of two points in this body in those two states expresses the numerical value of strain. Strain therefore expresses itself as a change in size and/or shape. [Wikipedia]
http://www.freestudy.co.uk/mech%20prin%20h2/stress.pdf
Strain
Defined as the 'work done' for a given strain, that is the area under the stress-strain curve after a specified eation. Source(s): http://www.prepol.com/product-range/product-subpages/terminology
u
Strain Energy Density
Stress is a measure of the average amount of force exerted per unit area of a surface within a deformable body on which internal forces act. In other words, it is a measure of the intensity or internal distribution of the total internal forces acting within a deformable body across imaginary surfaces. These internal forces are produced between the particles in the body as a reaction to external forces applied on the body. Stress is defined as \({\rm{Stress}} = \frac{F}{A}\).
\({\rm{Stress}} = \frac{F}{A}\)
\(\sigma\)
http://www.freestudy.co.uk/mech%20prin%20h2/stress.pdf
Stress
\(\gamma\)
Structural efficiency is a function of the weight of structure to the afforded vehicle's strength.
Structural Efficiency
http://en.wikipedia.org/wiki/Structure_factor
http://www.iso.org/iso/catalogue_detail?csnumber=31897
\(F(h, k, l) = \sum_{n=1}^N f_n\exp{[2\pi i(hx_n + ky_n +lz_n)]}\), where \(f_n\) is the atomic scattering factor for atom \(n\), and \(x_n\), \(y_n\), and \(z_n\) are fractional coordinates in the unit cell; for \(h\), \(k\), and \(l\).
"Structure Factor" is a mathematical description of how a material scatters incident radiation.
F(h, k, l)
Structure Factor
http://en.wikipedia.org/wiki/Superconductivity
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Superconduction Transition Temperature" is the critical thermodynamic temperature of a superconductor.
T_c
Superconduction Transition Temperature
http://en.wikipedia.org/wiki/BCS_theory
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Superconductor Energy Gap" is the width of the forbidden energy band in a superconductor.
Δ
Superconductor Energy Gap
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(a_s = \frac{A}{S}\), where \(S\) is the total area of the surface of a sample and \(A\) is its activity.
The "Surface Activity Density" is undefined.
a_s
Surface Activity Density
\(surface-heat-xfer-coeff\)
http://www.iso.org/iso/catalogue_detail?csnumber=31890
\(q = h (T_s - T_r)\), where \(T_s\) is areic heat flow rate is the thermodynamic temperature of the surface, and is a reference thermodynamic temperature characteristic of the adjacent surroundings.
\(\alpha\)
Surface Coefficient of Heat Transfer
\(kg m^{-2}\)
http://en.wikipedia.org/wiki/Area_density
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(\rho_A = \frac{dm}{dA}\), where \(m\) is mass and \(A\) is area.
\(\rho_A\)
The area density (also known as areal density, surface density, or superficial density) of a two-dimensional object is calculated as the mass per unit area.
Surface Density
\(n m^{-1}\)
http://en.wikipedia.org/wiki/Surface_tension
\(\gamma = \frac{dF}{dl}\), where \(F\) is the force component perpendicular to a line element in a surface and \(l\) is the length of the line element.
http://www.iso.org/iso/catalogue_detail?csnumber=31889
"Surface Tension" is a contractive tendency of the surface of a liquid that allows it to resist an external force.
γ
Surface Tension
http://dbpedia.org/resource/Susceptance
http://en.wikipedia.org/wiki/Susceptance?oldid=430151986
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=131-12-54
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(B = \lim{\underline{Y}}\), where \(\underline{Y}\) is admittance.
"Susceptance" is the imaginary part of admittance. The inverse of admittance is impedance and the real part of admittance is conductance.
B
Susceptance
http://www.oxfordreference.com/view/10.1093/acref/9780199549351.001.0001/acref-9780199549351-e-1162
The pressure of blood in the arteries which rises to a maximum as blood is pumped out by the left ventricle (systole) and drops to a minimum in diastole. The systolic/diastolic pressure is normally ~120/80 mmHg in a young adult.
Systolic Blood Pressure
An informal mass limit established by a Project Office (at the Element Integrated Product Team (IPT) level or below) to control mass.
Target Bogie Mass
http://dbpedia.org/resource/Temperature
Temperature is a physical property of matter that quantitatively expresses the common notions of hot and cold. Objects of low temperature are cold, while various degrees of higher temperatures are referred to as warm or hot. Heat spontaneously flows from bodies of a higher temperature to bodies of lower temperature, at a rate that increases with the temperature difference and the thermal conductivity.
Temperature
\(K \cdot mol\)
\(\Theta \cdot M\)
Temperature Amount of Substance
\(A \cdot K \cdot s^2/kg\)
\(\Theta \cdot I \cdot T^2/M\)
Temperature per Magnetic Flux Density
\(K/s\)
\(\Theta/T\)
Temperature per Time
Temperature Ratio
http://www.iso.org/iso/catalogue_detail?csnumber=43012
"Temporal Summation Function" is the ability of the human eye to produce a composite signal from the signals coming into an eye during a short time interval.
Temporal Summation Function
http://dbpedia.org/resource/Tension
Tension
http://en.wikipedia.org/wiki/Thermal_insulation
http://www.iso.org/iso/catalogue_detail?csnumber=31890
\(G = 1/R\), where \(R\) is "Thermal Resistance"
This quantity is also called "Heat Transfer Coefficient".
G
Thermal Conductance
In physics, thermal conductivity, \(k\) (also denoted as \(\lambda\)), is the property of a material's ability to conduct heat. It appears primarily in Fourier's Law for heat conduction and is the areic heat flow rate divided by temperature gradient.
\(L \cdot M/\Theta \cdot T^3\)
\(kg \cdot m/K \cdot s^3\)
http://dbpedia.org/resource/Thermal_conductivity
\(thermal-k\)
http://en.wikipedia.org/wiki/Thermal_conductivity
\(\lambda = \frac{\varphi}{T}\), where \(\varphi\) is areic heat flow rate and \(T\) is temperature gradient.
\(\lambda\)
Thermal Conductivity
http://www.thermopedia.com/content/1189/
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(\alpha_T = \frac{k_T}{(x_A x_B)}\), where \(k_T\) is the thermal diffusion ratio, and \(x_A\) and \(x_B\) are the local amount-of-substance fractions of the two substances \(A\) and \(B\).
\(\alpha_T\)
Thermal diffusion is a phenomenon in which a temperature gradient in a mixture of fluids gives rise to a flow of one constituent relative to the mixture as a whole. in the context of the equation that describes thermal diffusion, the "Thermal Diffusion Factor" is .
Thermal Diffusion Factor
http://www.thermopedia.com/content/1189/
http://www.iso.org/iso/catalogue_detail?csnumber=31894
In a steady state of a binary mixture in which thermal diffusion occurs, \(grad x_B = -(\frac{k_T}{T}) grad T\), where \(x_B\) is the amount-of-substance fraction of the heavier substance \(B\), and \(T\) is the local thermodynamic temperature.
The "Thermal Diffusion Ratio" is proportional to the product of the component concentrations.
k_T
Thermal Diffusion Ratio
http://www.thermopedia.com/content/1189/
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(D_T = kT \cdot D\), where \(k_T\) is the thermal diffusion ratio, and \(D\) is the diffusion coefficient.
The "Thermal Diffusion Coefficient" is .
D_T
Thermal Diffusion Coefficient
In heat transfer analysis, thermal diffusivity (usually denoted \(\alpha\) but \(a\), \(\kappa\),\(k\), and \(D\) are also used) is the thermal conductivity divided by density and specific heat capacity at constant pressure. The formula is: \(\alpha = {k \over {\rho c_p}}\), where k is thermal conductivity (\(W/(\mu \cdot K)\)), \(\rho\) is density (\(kg/m^{3}\)), and \(c_p\) is specific heat capacity (\(\frac{J}{(kg \cdot K)}\)) .The denominator \(\rho c_p\), can be considered the volumetric heat capacity (\(\frac{J}{(m^{3} \cdot K)}\)).
http://dbpedia.org/resource/Thermal_diffusivity
http://en.wikipedia.org/wiki/Thermal_diffusivity
\(a = \frac{\lambda}{\rho c_\rho}\), where \(\lambda\) is thermal conductivity, \(\rho\) is mass density and \(c_\rho\) is specific heat capacity at constant pressure.
\(\alpha\)
a
Thermal Diffusivity
http://dbpedia.org/resource/Thermal_efficiency
http://www.iso.org/iso/catalogue_detail?csnumber=31890
Thermal efficiency is a dimensionless performance measure of a thermal device such as an internal combustion engine, a boiler, or a furnace. The input to the device is heat, or the heat-content of a fuel that is consumed. The desired output is mechanical work, or heat, or possibly both.
Thermal Efficiency
"Thermal Energy} is the portion of the thermodynamic or internal energy of a system that is responsible for the temperature of the system. From a macroscopic thermodynamic description, the thermal energy of a system is given by its constant volume specific heat capacity C(T), a temperature coefficient also called thermal capacity, at any given absolute temperature (T): \(U_{thermal} = C(T) \cdot T\).
http://dbpedia.org/resource/Thermal_energy
http://en.wikipedia.org/wiki/Thermal_energy
Thermal Energy
Thermal Energy Length
\(\textit{Thermal Insulance}\) is the reduction of heat transfer (the transfer of thermal energy between objects of differing temperature) between objects in thermal contact or in range of radiative influence. In building technology, this quantity is often called \(\textit{Thermal Resistance}\), with the symbol \(R\).
\(K \cdot s^3/kg\)
\(\Theta \cdot T^3/M\)
http://en.wikipedia.org/wiki/Thermal_insulation
\(M = 1/K\), where \(K\) is "Coefficient of Heat Transfer"
M
Thermal Insulance
\(\textit{Thermal Resistance}\) is a heat property and a measure of a temperature difference by which an object or material resists a heat flow (heat per time unit or thermal resistance). Thermal resistance is the reciprocal thermal conductance. the thermodynamic temperature difference divided by heat flow rate. Thermal resistance \(R\) has the units \(\frac{m^2 \cdot K}{W}\).
\(K \cdot s^3/kg \cdot m^2\)
\(\Theta \cdot T^3/L^2 \cdot M\)
http://dbpedia.org/resource/Thermal_resistance
http://en.wikipedia.org/wiki/Thermal_resistance
http://www.iso.org/iso/catalogue_detail?csnumber=31890
R
Thermal Resistance
The reciprocal of thermal conductivity is thermal resistivity, measured in \(kelvin-metres\) per watt (\(K \cdot m/W\)).
\(K \cdot s^3/kg \cdot m\)
\(\Theta \cdot T^3/L \cdot M\)
Thermal Resistivity
http://en.wikipedia.org/wiki/Four_factor_formula
http://www.iso.org/iso/catalogue_detail?csnumber=31895
The "Thermal Utilization Factor" in an infinite medium, is the ratio of the number of thermal absorbed in a fissionable nuclide or in a nuclear fuel, as specified, to the total number of thermal neutrons absorbed.
f
Thermal Utilization Factor
Probability that a neutron that gets absorbed does so in the fuel material.
f
Thermal Utilization Factor For Fission
http://www.iso.org/iso/catalogue_detail?csnumber=31897
\(G_n - G_s = \frac{1}{2}\frac{B_c^2 \cdot V}{\mu_0}\), where \(G_n\) and \(G_s\) are the Gibbs energies at zero magnetic flux density in a normal conductor and superconductor, respectively, \(\mu_0\) is the magnetic constant, and \(V\) is volume.
"Thermodynamic Critical Magnetic Flux Density" is the
B_c
Thermodynamic Critical Magnetic Flux Density
http://www.iso.org/iso/catalogue_detail?csnumber=31890
For a closed thermodynamic system, \(\Delta U = Q + W\), where \(Q\) is amount of heat transferred to the system and \(W\) is work done on the system provided that no chemical reactions occur.
U
Thermodynamic Energy
Thermodynamic Entropy is a measure of the unavailability of a system’s energy to do work. It is a measure of the randomness of molecules in a system and is central to the second law of thermodynamics and the fundamental thermodynamic relation, which deal with physical processes and whether they occur spontaneously. The dimensions of entropy are energy divided by temperature, which is the same as the dimensions of Boltzmann's constant (\(kB\)) and heat capacity. The SI unit of entropy is \(joule\ per\ kelvin\). [Wikipedia]
http://www.iso.org/iso/catalogue_detail?csnumber=31890
Thermodynamic Entropy
\(K\)
\(\Theta\)
http://dbpedia.org/page/Thermodynamic_temperature
\(\Theta\)
Thermodynamic temperature is the absolute measure of temperature and is one of the principal parameters of thermodynamics.
Temperature is a physical property of matter that quantitatively expresses the common notions of hot and cold.
In thermodynamics, in a system of which the entropy is considered as an independent externally controlled variable, absolute, or thermodynamic temperature is defined as the derivative of the internal energy with respect to the entropy. This is a base quantity in the International System of Quantities, ISQ, on which the International System of Units, SI, is based.
T
Thermodynamic Temperature
http://dbpedia.org/resource/Thickness
http://www.merriam-webster.com/dictionary/thickness
http://www.iso.org/iso/catalogue_detail?csnumber=43012
"Thickness" is the the smallest of three dimensions: length, width, thickness.
d
Thickness
http://www.daviddarling.info/encyclopedia/T/Thomson_effect.html
http://www.iso.org/iso/catalogue_detail?csnumber=31897
\(\mu\)
"Thomson Coefficient" represents Thomson heat power developed, divided by the electric current and the temperature difference.
Thomson Coefficient
Thrust is a reaction force described quantitatively by Newton's Second and Third Laws. When a system expels or accelerates mass in one direction the accelerated mass will cause a proportional but opposite force on that system.
The pushing or pulling force developed by an aircraft engine or a rocket engine.
The force exerted in any direction by a fluid jet or by a powered screw, as, the thrust of an antitorque rotor.
Specifically, in rocketry, \( F\,= m\cdot v\) where m is propellant mass flow and v is exhaust velocity relative to the vehicle. Also called momentum thrust.
http://dbpedia.org/resource/Thrust
Thrust is a reaction force described quantitatively by Newton's Second and Third Laws. When a system expels or accelerates mass in one direction the accelerated mass will cause a proportional but opposite force on that system.
Thrust
The thrust force of a jet-propulsion engine per unit of frontal area per unit of incompressible dynamic pressure
C_{F}
Thrust Coefficient
\(L/T^2\)
\(m/s^2\)
Thrust To Mass Ratio
\(\psi\)
Thrust-to-weight ratio is a ratio of thrust to weight of a rocket, jet engine, propeller engine, or a vehicle propelled by such an engine. It is a dimensionless quantity and is an indicator of the performance of the engine or vehicle.
Thrust To Weight Ratio
\(\eta\)
Thruster Power To Thrust Efficiency
\(T\)
\(s\)
http://dbpedia.org/resource/Time
Time is a basic component of the measuring system used to sequence events, to compare the durations of events and the intervals between them, and to quantify the motions of objects.
t
Time
w/m2
http://en.wikipedia.org/wiki/Sound_intensity
\(I = \frac{1}{t2 - t1} \int_{t1}^{t2}i(t)dt\), where \(t1\) and \(t2\) are the starting and ending times for the integral and \(i\) is sound intensity.
Sound intensity or acoustic intensity (\(I\)) is defined as the sound power \(P_a\) per unit area \(A\). The usual context is the noise measurement of sound intensity in the air at a listener's location as a sound energy quantity.
I
belongs to SOQ-ISO
Time averaged sound intensity
Time Percentage
\(T^2\)
\(s^2\)
http://dbpedia.org/resource/Time_Squared
Time Squared
\(K \cdot s\)
\(\Theta \cdot T\)
http://www.iso.org/iso/catalogue_detail?csnumber=31890
Time Temperature
In physics, a torque (\(\tau\)) is a vector that measures the tendency of a force to rotate an object about some axis. The magnitude of a torque is defined as force times its lever arm. Just as a force is a push or a pull, a torque can be thought of as a twist. The SI unit for torque is newton meters (\(N m\)). In U.S. customary units, it is measured in foot pounds (ft lbf) (also known as "pounds feet").
Mathematically, the torque on a particle (which has the position r in some reference frame) can be defined as the cross product: \(τ = r x F\)
where,
r is the particle's position vector relative to the fulcrum
F is the force acting on the particles,
or, more generally, torque can be defined as the rate of change of angular momentum: \(τ = dL/dt\)
where,
L is the angular momentum vector
t stands for time.
\(L^2 \cdot M/T^2\)
\(kg \cdot m^2/s^2\)
http://dbpedia.org/resource/Torque
http://en.wikipedia.org/wiki/Torque
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(\tau = M \cdot e_Q\), where \(M\) is the momentof force and \(e_Q\) is a unit vector directed along a \(Q-axis\) with respect to which the torque is considered.
\(\tau\)
http://en.wikipedia.org/wiki/Torque
Torque
"Total Angular Momentum" combines both the spin and orbital angular momentum of all particles and fields. In atomic and nuclear physics, orbital angular momentum is usually denoted by \(l\) or \(L\) instead of \(\Lambda\). The magnitude of \(J\) is quantized so that \(J^2 = \hbar^2 j(j + 1)\), where \(j\) is the total angular momentum quantum number.
http://en.wikipedia.org/wiki/Angular_momentum#Spin.2C_orbital.2C_and_total_angular_momentum
http://www.iso.org/iso/catalogue_detail?csnumber=31895
J
Total Angular Momentum
The "Total Angular Quantum Number" describes the magnitude of total angular momentum \(J\), where \(j\) refers to a specific particle and \(J\) is used for the whole system.
http://en.wikipedia.org/wiki/Quantum_number
http://www.iso.org/iso/catalogue_detail?csnumber=31894
j
Total Angular Momentum Quantum Number
http://www.answers.com/topic/atomic-stopping-power
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(S_a = \frac{S}{n}\), where \(S\) is the total linear stopping power and \(n\) is the number density of the atoms in the substance.
The "Total Atomic Stopping Power" for an ionizing particle passing through an element, is the particle's energy loss per atom within a unit area normal to the particle's path; equal to the linear energy transfer (energy loss per unit path length) divided by the number of atoms per unit volume.
S_a
Total Atomic Stopping Power
http://en.wikipedia.org/wiki/Cross_section_(physics)
http://www.iso.org/iso/catalogue_detail?csnumber=31895
"Total Cross-section" is related to the absorbance of the light intensity through Beer-Lambert's law. It is the sum of all cross-sections corresponding to the various reactions or processes between an incident particle of specified type and energy and a target particle.
σₜ
Total Cross-section
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(I_{tot}= I + I_D\), where \(I\) is electric current and \(I_D\) is displacement current.
"Total Current" is the sum of the electric current that is flowing through a surface and the displacement current.
I_t
I_{tot}
Total Current
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(J_{tot}= J + J_D\), where \(J\) is electric current density and \(J_D\) is displacement current density.
\(J_{tot}\)
"Total Current Density" is the sum of the electric current density and the displacement current density.
Total Current Density
"Total Ionization" by a particle, total mean charge, divided by the elementary charge, \(e\), of all positive ions produced by an ionizing charged particle along its entire path and along the paths of any secondary charged particles.
http://en.wikipedia.org/wiki/Ionization#Classical_ionization
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(N = \int N_i dl\).
N_i
Total Ionization
http://en.wikipedia.org/wiki/Stopping_power_(particle_radiation)
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(S = -\frac{dE}{dx}\), where \(-dE\) is the energy decrement in the \(x-direction\) along an elementary path with the length \(dx\).
The "Total Linear Stopping Power" is defined as the average energy loss of the particle per unit path length.
S
Total Linear Stopping Power
http://en.wikipedia.org/wiki/Stopping_power_(particle_radiation)
http://www.iso.org/iso/catalogue_detail?csnumber=31895
\(S_m = \frac{S}{\rho}\), where \(S\) is the total linear stopping power and \(\rho\) is the mass density of the sample.
If a substance is compared in gaseous and solid form, then the linear stopping powers of the two states are very different just because of the different density. One therefore often divides S(E) by the density of the material to obtain the "Mass Stopping Power". The mass stopping power then depends only very little on the density of the material.
S_m
Total Mass Stopping Power
The total pressure is the sum of the dynamic and static pressures, that is \(P_0 = P + q\).
P_0
Total Pressure
http://www.iso.org/iso/catalogue_detail?csnumber=43012
\(\overline{T_t}\)
"Touch Thresholds" are thresholds for touch, vibration and other stimuli to the skin.
Touch Thresholds
\(\tau = \frac{\Phi_t}{\Phi_m}\), where \(\Phi_t\) is the transmitted radiant flux or the transmitted luminous flux, and \(\Phi_m\) is the radiant flux or luminous flux of the incident radiation.
\(\tau, T\)
Transmittance is the fraction of incident light (electromagnetic radiation) at a specified wavelength that passes through a sample.
belongs to SOQ-ISO
Transmittance
\(A_{10}(\lambda) = -lg(\tau(\lambda))\), where \(\tau\) is the transmittance at a given wavelength \(\lambda\).
Transmittance is the fraction of incident light (electromagnetic radiation) at a specified wavelength that passes through a sample.
A_10, D
Transmittance Density
u_{e}
True Exhaust Velocity
http://dbpedia.org/resource/Turbidity
http://en.wikipedia.org/wiki/Turbidity
Turbidity is the cloudiness or haziness of a fluid, or of air, caused by individual particles (suspended solids) that are generally invisible to the naked eye, similar to smoke in air. Turbidity in open water is often caused by phytoplankton and the measurement of turbidity is a key test of water quality. The higher the turbidity, the higher the risk of the drinkers developing gastrointestinal diseases, especially for immune-compromised people, because contaminants like virus or bacteria can become attached to the suspended solid. The suspended solids interfere with water disinfection with chlorine because the particles act as shields for the virus and bacteria. Similarly suspended solids can protect bacteria from UV sterilisation of water. Fluids can contain suspended solid matter consisting of particles of many different sizes. While some suspended material will be large enough and heavy enough to settle rapidly to the bottom container if a liquid sample is left to stand (the settleable solids), very small particles will settle only very slowly or not at all if the sample is regularly agitated or the particles are colloidal. These small solid particles cause the liquid to appear turbid.
Turbidity
"Turns" is the number of turns in a winding.
N
Turns
The gas constant (also known as the molar, universal, or ideal gas constant) is a physical constant which is featured in many fundamental equations in the physical sciences, such as the ideal gas law and the Nernst equation.
Physically, the gas constant is the constant of proportionality that happens to relate the energy scale in physics to the temperature scale, when a mole of particles at the stated temperature is being considered.
R
Universal Gas Constant
http://www.iso.org/iso/catalogue_detail?csnumber=31897
"Upper Critical Magnetic Flux Density" for type II superconductors, is the threshold magnetic flux density for disappearance of bulk superconductivity.
B_{c2}
Upper Critical Magnetic Flux Density
\(VT\)
Vacuum Thrust
V
Vehicle Velocity
http://dbpedia.org/resource/Velocity
http://en.wikipedia.org/wiki/Velocity
In kinematics, velocity is the speed of an object and a specification of its direction of motion. Speed describes only how fast an object is moving, whereas velocity gives both how fast and in what direction the object is moving.
v
Velocity
The rate at which a body moves upwards at an angle of 90 degrees to the ground. It is the component of a projectile's velocity which is concerned with lifting the projectile.
V_{Z}
Vertical Velocity
http://en.wikipedia.org/wiki/Frame_rate
Frame rate (also known as frame frequency) is the frequency (rate) at which an imaging device produces unique consecutive images called frames. The term applies equally well to computer graphics, video cameras, film cameras, and motion capture systems. Frame rate is most often expressed in frames per second (FPS) and is also expressed in progressive scan monitors as hertz (Hz).
Video Frame Rate
http://dbpedia.org/resource/Viscosity
Viscosity is a measure of the resistance of a fluid which is being deformed by either shear stress or extensional stress. In general terms it is the resistance of a liquid to flow, or its "thickness". Viscosity describes a fluid's internal resistance to flow and may be thought of as a measure of fluid friction. [Wikipedia]
Viscosity
http://en.wikipedia.org/wiki/Radiant_energy
http://www.iso.org/iso/catalogue_detail?csnumber=31892
Q
"Visible Radiant Energy", also known as luminous energy, is the energy of electromagnetic waves. It is energy of the particles that are emitted, transferred, or received as radiation.
Q
Visible Radiant Energy
http://www.iso.org/iso/catalogue_detail?csnumber=43012
\(\overline{T_v}\)
"Vision Threshods" is the thresholds of sensitivity of the eye.
Vision Threshods
\(\textit{Voltage}\), also referred to as \(\textit{Electric Tension}\), is the difference between electrical potentials of two points. For an electric field within a medium, \(U_{ab} = - \int_{r_a}^{r_b} E . {dr}\), where \(E\) is electric field strength.
For an irrotational electric field, the voltage is independent of the path between the two points \(a\) and \(b\).
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(U_{ab} = V_a - V_b\), where \(V_a\) and \(V_b\) are electric potentials at points \(a\) and \(b\), respectively.
\(U_{ab}\)
U
Voltage
Voltage Percentage
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=131-11-26
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
When \(u = \hat{U} \cos{(\omega t + \alpha)}\), where \(u\) is the voltage, \(\omega\) is angular frequency, \(t\) is time, and \(\alpha\) is initial phase, then \(\underline{U} = Ue^{ja}\).
\(\underline{U}\)
"Voltage Phasor" is a representation of voltage as a sinusoidal integral quantity using a complex quantity whose argument is equal to the initial phase and whose modulus is equal to the root-mean-square value. A phasor is a constant complex number, usually expressed in exponential form, representing the complex amplitude (magnitude and phase) of a sinusoidal function of time. Phasors are used by electrical engineers to simplify computations involving sinusoids, where they can often reduce a differential equation problem to an algebraic one.
Voltage Phasor
\(L^3\)
\(m^3\)
http://dbpedia.org/resource/Volume
The volume of a solid object is the three-dimensional concept of how much space it occupies, often quantified numerically. One-dimensional figures (such as lines) and two-dimensional shapes (such as squares) are assigned zero volume in the three-dimensional space.
Volume
\(m^{3} sec^{-1}\)
http://en.wikipedia.org/wiki/Volumetric_flow_rate
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(q_V = \frac{dV}{dt}\), where \(V\) is volume and \(t\) is time.
Volumetric Flow Rate, (also known as volume flow rate, rate of fluid flow or volume velocity) is the volume of fluid which passes through a given surface per unit time.
q_V
Volume Flow Rate
http://en.wikipedia.org/wiki/Volume_fraction
http://www.iso.org/iso/catalogue_detail?csnumber=31894
\(\varphi_B = \frac{x_B V_{m,B}^*}{\sum x_i V_{m,i}^*}\), where \(V_{m,i}^*\) is the molar volume of the pure substances \(i\) at the same temperature and pressure, \(x_i\) denotes the amount-of-substance fraction of substance \(i\), and \(\sum\) denotes summation over all substances \(i\).
\(\varphi_B\)
"Volume Fraction" is the volume of a constituent divided by the volume of all constituents of the mixture prior to mixing. Volume fraction is also called volume concentration in ideal solutions where the volumes of the constituents are additive (the volume of the solution is equal to the sum of the volumes of its ingredients).
Volume Fraction
\(L^3/T\)
\(m^3/s\)
Volume per Unit Time
Volume, or volumetric, Strain, or dilatation (the relative variation of the volume) is the trace of the tensor \(\vartheta\).
http://en.wikipedia.org/wiki/Deformation_(mechanics)
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(\vartheta = \frac{\Delta V}{V_0}\), where \(\Delta V\) is the increase in volume and \(V_0\) is the volume in a reference state to be specified.
\(\vartheta\)
Volume Strain
\(L^3/\Theta\)
\(m^3/K\)
When the temperature of a substance changes, the energy that is stored in the intermolecular bonds between atoms changes. When the stored energy increases, so does the length of the molecular bonds. As a result, solids typically expand in response to heating and contract on cooling; this dimensional response to temperature change is expressed by its coefficient of thermal expansion.
Different coefficients of thermal expansion can be defined for a substance depending on whether the expansion is measured by:
* linear thermal expansion
* area thermal expansion
* volumetric thermal expansion
These characteristics are closely related. The volumetric thermal expansion coefficient can be defined for both liquids and solids. The linear thermal expansion can only be defined for solids, and is common in engineering applications.
Some substances expand when cooled, such as freezing water, so they have negative thermal expansion coefficients. [Wikipedia]
Volume Thermal Expansion
https://en.wikipedia.org/wiki/Volumetric_flux
In fluid dynamics, the volumetric flux is the rate of volume flow across a unit area (m3·s−1·m−2).[Wikipedia]
Volumetric Flux
\(\textit{Volumetric Heat Capacity (VHC)}\), also termed \(\textit{volume-specific heat capacity}\), describes the ability of a given volume of a substance to store internal energy while undergoing a given temperature change, but without undergoing a phase transition. It is different from specific heat capacity in that the VHC is a \(\textit{per unit volume}\) measure of the relationship between thermal energy and temperature of a material, while the specific heat is a \(\textit{per unit mass}\) measure (or occasionally per molar quantity of the material).
\(M/\Theta \cdot L \cdot T^2\)
\(kg/K \cdot m \cdot s^2\)
http://dbpedia.org/resource/Volumetric_heat_capacity
http://en.wikipedia.org/wiki/Volumetric_heat_capacity
Volumetric Heat Capacity
\(\textit{Volumic Electromagnetic Energy}\), also known as the \(\textit{Electromagnetic Energy Density}\), is the energy associated with an electromagnetic field, per unit volume of the field.
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=121-11-64
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
\(w = (1/2) ( \mathbf{E} \cdot \mathbf{D} + \mathbf{B} \cdot \mathbf{H})\), where \(\mathbf{E}\) is electric field strength, \(\mathbf{D}\) is electric flux density, \(\mathbf{M}\) is magnetic flux density, and \(\mathbf{H}\) is magnetic field strength.
\(w\)
Volumic Electromagnetic Energy
\(\omega\)
In the simplest sense, vorticity is the tendency for elements of a fluid to "spin." More formally, vorticity can be related to the amount of "circulation" or "rotation" (or more strictly, the local angular rate of rotation) in a fluid. The average vorticity in a small region of fluid flow is equal to the circulation C around the boundary of the small region, divided by the area A of the small region. Mathematically, vorticity is a vector field and is defined as the curl of the velocity field.
Vorticity
http://www.iso.org/iso/catalogue_detail?csnumber=43012
\(\overline{T_w}\)
"Warm Receptor Threshold" is the threshold of warm-sensitive free nerve-ending.
Warm Receptor Threshold
No pump can convert all of its mechanical power into water power. Mechanical power is lost in the pumping process due to friction losses and other physical losses. It is because of these losses that the horsepower going into the pump has to be greater than the water horsepower leaving the pump. The efficiency of any given pump is defined as the ratio of the water horsepower out of the pump compared to the mechanical horsepower into the pump.
https://www.uaex.edu/environment-nature/water/docs/IrrigSmart-3241-A-Understanding-water-horsepower.pdf
Water Horsepower
For a monochromatic wave, "wavelength" is the distance between two successive points in a direction perpendicular to the wavefront where at a given instant the phase differs by \(2\pi\). The wavelength of a sinusoidal wave is the spatial period of the wave—the distance over which the wave's shape repeats. The SI unit of wavelength is the meter.
http://en.wikipedia.org/wiki/Wavelength
\(\lambda = \frac{c}{\nu}\), where \(\lambda\) is the wave length, \(\nu\) is the frequency, and \(c\) is the speed of light in the medium.
λ
belongs to SOQ-ISO
Wavelength
http://en.wikipedia.org/wiki/Wavenumber
\(\sigma = \frac{\nu}{c}\), where \(\sigma\) is the wave number, \(\nu\) is the frequency, and \(c\) is the speed of light in the medium.
Or:
\(k = \frac{2\pi}{\lambda}= \frac{2\pi\upsilon}{\upsilon_p}=\frac{\omega}{\upsilon_p}\), where \(\upsilon\) is the frequency of the wave, \(\lambda\) is the wavelength, \(\omega = 2\pi \upsilon\) is the angular frequency of the wave, and \(\upsilon_p\) is the phase velocity of the wave.
\(\sigma\)
"Wavenumber" is the spatial frequency of a wave - the number of waves that exist over a specified distance. More formally, it is the reciprocal of the wavelength. It is also the magnitude of the wave vector. Light passing through different media keeps its frequency, but not its wavelength or wavenumber. The unit for wavenumber commonly used in spectroscopy is centimetre to power minus one, PER-CM, rather than metre to power minus one, PER-M.
Wavenumber
Web Time
Web Time
Web Time Average Pressure
Web Time Avg Thrust (Mlbf)
Web Time Average Thrust
http://dbpedia.org/resource/Weight
The force with which a body is attracted toward an astronomical body. Or, the product of the mass of a body and the acceleration acting on a body. In a dynamic situation, the weight can be a multiple of that under resting conditions. Weight also varies on other planets in accordance with their gravity.
bold letter W
http://en.wikipedia.org/wiki/Weight
Weight
"Width" is the middle of three dimensions: length, width, thickness.
Width
The net work is equal to the change in kinetic energy. This relationship is called the work-energy theorem: \(Wnet = K. E._f − K. E._o \), where \(K. E._f\) is the final kinetic energy and \(K. E._o\) is the original kinetic energy. Potential energy, also referred to as stored energy, is the ability of a system to do work due to its position or internal structure. Change in potential energy is equal to work. The potential energy equations can also be derived from the integral form of work, \(\Delta P. E. = W = \int F \cdot dx\).
\(L^2 \cdot M/T^2\)
http://en.wikipedia.org/wiki/Work_(physics)
http://www.cliffsnotes.com/study_guide/Work-and-Energy.topicArticleId-10453,articleId-10418.html
http://www.iso.org/iso/catalogue_detail?csnumber=31889
\(A = \int Pdt\), where \(P\) is power and \(t\) is time.
A force is said to do Work when it acts on a body so that there is a displacement of the point of application, however small, in the direction of the force. The concepts of work and energy are closely tied to the concept of force because an applied force can do work on an object and cause a change in energy. Energy is defined as the ability to do work. Work is done on an object when an applied force moves it through a distance. Kinetic energy is the energy of an object in motion. The net work is equal to the change in kinetic energy.
A
Work
http://en.wikipedia.org/wiki/Work_function
http://www.iso.org/iso/catalogue_detail?csnumber=31897
\(\Phi\)
"Work Function" is the energy difference between an electron at rest at infinity and an electron at a certain energy level. The minimum energy (usually measured in electronvolts) needed to remove an electron from a solid to a point immediately outside the solid surface (or energy needed to move an electron from the Fermi level into vacuum).
Work Function
QUDT Quantity Kinds Vocabulary Catalog Entry v1.2
Jack Hodges
Steve Ray
2019-08-01T16:25:54.850+00:00
Ralph Hodgson
Steve Ray
Provides the set of all quantity kinds.
2021-11-02T09:58:34.623-07:00
The QUDT Ontologies are issued under a Creative Commons Attribution 4.0 International License (CC BY 4.0), available at https://creativecommons.org/licenses/by/4.0/. Attribution should be made to QUDT.org
QUANTITY-KINDS-ALL
All disciplines
Science, Medicine and Engineering
2019-08-01T21:26:38
QUDT Quantity Kinds Version 2.1.14
TBD
http://www.qudt.org/doc/2021/11/DOC_VOCAB-QUANTITY-KINDS-ALL-v2.1.html
http://www.linkedmodel.org/lib/lm/images/logos/qudt_logo-300x110.png
http://qudt.org/vocab/quantitykind/
quantitykind
qudt.org
http://www.qudt.org/doc/2021/09/DOC_VOCAB-QUANTITY-KINDS-ALL-v2.1.html
2.1
1
http://qudt.org/2.1/vocab/quantitykind
QUDT Quantity Kinds Vocabulary Version 2.1.14