Physical Quantities
Base units
| Quantity | Name | Symbol |
|---|---|---|
| time | second | \(\mathrm{s}\) |
| length | metre | \(\mathrm{m}\) |
| mass | kilogram | \(\mathrm{kg}\) |
| electric current | ampere | \(\mathrm{A}\) |
| temperature | kelvin | \(\mathrm{K}\) |
| amount of substance | mole | \(\mathrm{mol}\) |
| luminous intensity | candela | \(\mathrm{cd}\) |
Derived units
Special name units
| Quantity | Name | Symbol | Equivalents | SI Equivalents |
|---|---|---|---|---|
| frequency | hertz | \(\mathrm{Hz}\) | \(\mathrm{ 1 / s }\) | \(\mathrm{ s^{-1}}\) |
| angle | radian | \(\mathrm{rad}\) | \(\mathrm{m / m}\) | \( 1 \) |
| solid angle | esteradian | \(\mathrm{sr}\) | \(\mathrm{m^{2} / m^{2}}\) | \( 1 \) |
| force, weight | newton | \(\mathrm{N}\) | \(\mathrm{kg \cdot m/s^{2}}\) | \(\mathrm{kg \cdot m \cdot s^{-2}}\) |
| pressure, stress | pascal | \(\mathrm{Pa}\) | \(\mathrm{N/m^{2}}\) | \(\mathrm{kg \cdot m^{-1} \cdot s^{-2}}\) |
| energy, work, heat | joule | \(\mathrm{J}\) | \(\mathrm{m \cdot N,\ C \cdot V,\ W \cdot s}\) | \(\mathrm{kg \cdot m^{2} \cdot s^{-2} }\) |
| power, radiant flux | watt | \(\mathrm{W}\) | \(\mathrm{J/s, V \cdot A}\) | \(\mathrm{kg \cdot m^{2} \cdot s^{-3} }\) |
| electric charge | coulomb | \(\mathrm{C}\) | \(\mathrm{s \cdot A, F \cdot V}\) | \(\mathrm{s \cdot A}\) |
| voltage, electrical potential difference, electromotive force | volt | \(\mathrm{V}\) | \(\mathrm{W/A, J/C}\) | \(\mathrm{kg \cdot m^{2} \cdot s^{-3}\cdot A^{-1}}\) |
| electrical capacitance | farad | \(\mathrm{F}\) | \(\mathrm{C/V, s/\Omega}\) | \(\mathrm{kg^{-1}\cdot m^{-2} \cdot s^{4} \cdot A^{2}}\) |
| electrical resistance, impedance, reactance | ohm | \(\Omega\) | \(\mathrm{1/S, V/A}\) | \(\mathrm{kg \cdot m^{2} \cdot s^{-3}⋅A^{-2}}\) |
| electrical conductance | siemens | \(\mathrm{S}\) | \(\mathrm{1/ \Omega, A/V}\) | \(\mathrm{kg^{-1} \cdot m^{-2} \cdot s^{3} \cdot A^{2} }\) |
| magnetic flux | weber | \(\mathrm{Wb}\) | \(\mathrm{J/A, T \cdot m^{2},V \cdot s}\) | \(\mathrm{kg \cdot m^{2} \cdot s^{-2} \cdot A^{-1} }\) |
| magnetic induction, magnetic flux density | tesla | \(\mathrm{T}\) | \(\mathrm{V \cdot s/m^{2}, Wb/m^{2}, N/(A \cdot m)}\) | \(\mathrm{kg \cdot s^{-2} \cdot A^{-1} }\) |
| electrical inductance | henry | \(\mathrm{H}\) | \(\mathrm{V \cdot s/A, \Omega \cdot s, Wb/A}\) | \(\mathrm{kg \cdot m^{2} \cdot s^{-2} \cdot A^{-2}}\) |
| temperature relative to \(273.15\ \mathrm{K}\) | degree Celsius | \( ^{\circ}\mathrm{C} \) | \(\mathrm{K}\) | \(\mathrm{K}\) |
| luminous flux | lumen | \(\mathrm{lm}\) | \(\mathrm{cd \cdot sr}\) | \(\mathrm{cd}\) |
| illuminance | lux | \(\mathrm{lx}\) | \(\mathrm{ lm/m^{2}}\) | \(\mathrm{cd \cdot m^{-2}}\) |
| radioactivity | becquerel | \(\mathrm{Bq}\) | \(\mathrm{1/s}\) | \(\mathrm{s^{-1}}\) |
| absorbed dose | gray | \(\mathrm{Gy}\) | \(\mathrm{J/kg}\) | \(\mathrm{m^{2} \cdot s^{-2}}\) |
| equivalent dose | sievert | \(\mathrm{Sv}\) | \(\mathrm{J/kg}\) | \(\mathrm{m^{2} \cdot s^{-2}}\) |
| catalytic activity | katal | \(\mathrm{kat}\) | \(\mathrm{mol/s}\) | \(\mathrm{s^{-1} \cdot mol}\) |
By field of application
Kinematics
| Quantity | Name | Symbol | SI Equivalents |
|---|---|---|---|
| speed, velocity | metre per second | \(\mathrm{m/s}\) | \(\mathrm{m \cdot s^{-1}}\) |
| acceleration | metre per second squared | \(\mathrm{m/s^{2}}\) | \(\mathrm{m \cdot s^{-2}}\) |
| jerk, jolt | metre per second cubed | \(\mathrm{m/s^{3}}\) | \(\mathrm{m \cdot s^{-3}}\) |
| snap,jounce | metre per second to the fourth | \(\mathrm{m/s^{4}}\) | \(\mathrm{m \cdot s^{-4}}\) |
| crackle | metre per second to the fifth | \(\mathrm{m/s^{5}}\) | \(\mathrm{m \cdot s^{-5}}\) |
| pop | metre per second to the sixth | \(\mathrm{m/s^{6}}\) | \(\mathrm{m \cdot s^{-6}}\) |
| angular velocity | radian per second | \(\mathrm{rad/s}\) | \(\mathrm{s^{-1}}\) |
| angular acceleration | radian per second squared | \(\mathrm{rad/s^{2}}\) | \(\mathrm{s^{-2}}\) |
| frequency drift | hertz per second | \(\mathrm{Hz/s}\) | \(\mathrm{s^{-2}}\) |
| volumetric flow | cubic metre per second | \(\mathrm{m^{3}/s}\) | \(\mathrm{m^{3} \cdot s^{-1}}\) |
Mechanics
| Quantity | Name | Symbol | SI Equivalents |
|---|---|---|---|
| area | square metre | \(\mathrm{m^{2}}\) | \(\mathrm{m^{2}}\) |
| volume | cubic metre | \(\mathrm{m^{3}}\) | \(\mathrm{m^{3}}\) |
| momentum, impulse | newton-second | \(\mathrm{N \cdot s}\) | \(\mathrm{m \cdot kg \cdot s^{-1}}\) |
| angular momentum | newton metre second | \(\mathrm{N \cdot m \cdot s}\) | \(\mathrm{m^{2} \cdot kg \cdot s^{-1}}\) |
| torque, moment of force | newton-metre | \(\mathrm{N \cdot m = J/rad}\) | \(\mathrm{m^{2} \cdot kg \cdot s^{-2}}\) |
| yank | newton per second | \(\mathrm{N/s}\) | \(\mathrm{m \cdot kg \cdot s^{-3}}\) |
| wavenumber, optical power, curvature, spatial frequency | reciprocal metre | \(\mathrm{m^{-1}}\) | \(\mathrm{m^{-1}}\) |
| area density | kilogram per square metre | \(\mathrm{kg/m^{2}}\) | \(\mathrm{m^{2}\cdot kg}\) |
| density | kilogram per cubic metre | \(\mathrm{kg/m^{3}}\) | \(\mathrm{m^{-3} \cdot kg}\) |
| specific volume | cubic metre per kilogram | \(\mathrm{m^{3}/kg}\) | \(\mathrm{m^{3} \cdot kg^{-1}}\) |
| action | joule-second | \(\mathrm{J \cdot s}\) | \(\mathrm{m^{2} \cdot kg \cdot s^{-1}}\) |
| specific energy | joule per kilogram | \(\mathrm{J/kg}\) | \(\mathrm{m^{2} \cdot s^{-2}}\) |
| energy density | joule per cubic metre | \(\mathrm{J/m^{3}}\) | \(\mathrm{m^{-1} \cdot kg \cdot s^{-2}}\) |
| surface tension, stiffness | newton per metre | \(\mathrm{N/m = J/m^{2}}\) | \(\mathrm{kg \cdot s^{-2}}\) |
| heat flux density, irradiance | watt per square metre | \(\mathrm{W/m^{2}}\) | \(\mathrm{kg \cdot s^{-3}}\) |
| kinematic viscosity, thermal diffusivity, diffusion coefficient | square metre per second | \(\mathrm{m^{2}/s}\) | \(\mathrm{m^{2} \cdot s^{-1}}\) |
| dynamic viscosity | pascal-second | \(\mathrm{Pa \cdot s = N \cdot s/m^{2}}\) | \(\mathrm{m^{-1} \cdot kg \cdot s^{-1}}\) |
| linear mass density | kilogram per metre | \(\mathrm{kg/m}\) | \(\mathrm{m^{-1} \cdot kg}\) |
| mass flow rate | kilogram per second | \(\mathrm{kg/s}\) | \(\mathrm{kg \cdot s^{-1}}\) |
| radiance | watt per steradian square metre | \(\mathrm{W/\left(sr\cdot m^{2}\right)}\) | \(\mathrm{kg \cdot s^{-3}}\) |
| radiance | watt per steradian cubic metre | \(\mathrm{W/\left(sr\cdot m^{3}\right)}\) | \(\mathrm{m^{-1} kg \cdot s^{-3}}\) |
| spectral power | watt per metre | \(\mathrm{W/m}\) | \(\mathrm{m \cdot kg \cdot s^{-3}}\) |
| absorbed dose rate | gray per second | \(\mathrm{Gy/s}\) | \(\mathrm{m^{2} \cdot s^{-3}}\) |
| fuel efficiency | metre per cubic metre | \(\mathrm{m/m^{3}}\) | \(\mathrm{m^{-2}}\) |
| spectral irradiance, power density | watt per cubic metre | \(\mathrm{W/m^{3}}\) | \(\mathrm{m^{-1} \cdot kg \cdot s^{-3}}\) |
| energy flux density | joule per square metre second | \(\mathrm{J/\left( m^{2} \cdot s\right)}\) | \(\mathrm{kg \cdot s^{-3}}\) |
| compressibility | reciprocal pascal | \(\mathrm{Pa^{-1}}\) | \(\mathrm{m \cdot kg^{-1} \cdot s^{2}}\) |
| radiant exposure | joule per square metre | \(\mathrm{J/m^{2}}\) | \(\mathrm{kg \cdot s^{-2}}\) |
| moment of inertia | kilogram square metre | \(\mathrm{kg \cdot m^{2}}\) | \(\mathrm{m^{2} \cdot kg}\) |
| specific angular momentum | newton metre second per kilogram | \(\mathrm{N \cdot m \cdot s/kg}\) | \(\mathrm{m^{2} \cdot s^{-1}}\) |
| radiant intensity | watt per steradian | \(\mathrm{W/sr}\) | \(\mathrm{m^{2} \cdot kg \cdot s^{-3}}\) |
| spectral intensity | watt per steradian metre | \(\mathrm{W/\left( sr \cdot m \right)}\) | \(\mathrm{m \cdot kg \cdot s^{-3}}\) |
Chemistry
| Quantity | Name | Symbol | SI Equivalents |
|---|---|---|---|
| molarity, amount of substance concentration | mole per cubic metre | \(\mathrm{mol / m^{3}}\) | \(\mathrm{m^{-3} \cdot mol}\) |
| molar volume | cubic metre per mole | \(\mathrm{m^{3} / mol}\) | \(\mathrm{m^{3} \cdot mol^{-1}}\) |
| molar heat capacity, molar entropy | joule per kelvin mole | \(\mathrm{J/\left(K \cdot mol\right) }\) | \(\mathrm{m^{2} \cdot kg \cdot s^{-2} \cdot K^{-1} \cdot mol^{-1}}\) |
| molar energy | joule per mole | \(\mathrm{J/ mol}\) | \(\mathrm{m^{2} \cdot kg \cdot s^{-2} \cdot mol^{-1}}\) |
| molar conductivity | siemens square metre per mole | \(\mathrm{S \cdot m^{2} / mol}\) | \(\mathrm{kg^{-1} \cdot s^{3} \cdot A^{2} \cdot mol^{-1}}\) |
| molality | mole per kilogram | \(\mathrm{mol / kg}\) | \(\mathrm{kg^{-1} \cdot mol}\) |
| molar mass | kilogram per mole | \(\mathrm{kg/mol}\) | \(\mathrm{kg \cdot mol^{-1}}\) |
| catalytic efficiency | cubic metre per mole second | \(\mathrm{m^{3}/\left( mol \cdot s \right)}\) | \(\mathrm{m^{3} \cdot s^{-1} \cdot mol^{-1} }\) |
Electromagnetics
| Quantity | Name | Symbol | SI Equivalents |
|---|---|---|---|
| electric displacement field, polarization density | coulomb per square metre | \(\mathrm{C/m^{2}}\) | \(\mathrm{m^{-2} \cdot s \cdot A }\) |
| electric charge density | coulomb per cubic metre | \(\mathrm{C/m^{3}}\) | \(\mathrm{m^{-3} \cdot s \cdot A }\) |
| electric current density | ampere per square metre | \(\mathrm{A/m^{2}}\) | \(\mathrm{m^{-2} \cdot A}\) |
| electrical conductivity | siemens per metre | \(\mathrm{S/m}\) | \(\mathrm{m^{-3} \cdot kg^{-1} \cdot s^{3} \cdot A^{2}}\) |
| permittivity | farad per metre | \(\mathrm{F/m}\) | \(\mathrm{m^{-3} \cdot kg^{-1} \cdot s^{4} \cdot A^{2} }\) |
| magnetic permeability | henry per metre | \(\mathrm{H/m}\) | \(\mathrm{m \cdot kg \cdot s^{-2} \cdot A^{-2} }\) |
| electric field strength | volt per metre | \(\mathrm{V/m}\) | \(\mathrm{m \cdot kg \cdot s^{-3} \cdot A^{-2}}\) |
| magnetization, magnetic field strength | ampere per metre | \(\mathrm{A/m}\) | \(\mathrm{m^{-1} \cdot A }\) |
| exposure (X and \(\gamma\) rays) | coulomb per kilogram | \(\mathrm{C/kg}\) | \(\mathrm{kg^{-1} \cdot s \cdot A }\) |
| resistivity | ohm metre | \(\mathrm{\Omega \cdot m}\) | \(\mathrm{m^{3} \cdot kg \cdot s^{-3} \cdot A^{-2}}\) |
| linear charge density | coulomb per metre | \(\mathrm{C/m}\) | \(\mathrm{m^{-1} \cdot s \cdot A }\) |
| magnetic dipole moment | joule per tesla | \(\mathrm{J/T}\) | \(\mathrm{m^{2} \cdot A}\) |
| electron mobility | square metre per volt second | \(\mathrm{m^{2}/\left( V \cdot s \right)}\) | \(\mathrm{kg^{-1} \cdot s^{2} \cdot A }\) |
| magnetic reluctance | reciprocal henry | \(\mathrm{H^{-1}}\) | \(\mathrm{m^{-2} \cdot kg^{-1} \cdot s^{2} \cdot A^{2}}\) |
| magnetic vector potential | weber per metre | \(\mathrm{Wb/m}\) | \(\mathrm{m \cdot kg \cdot s^{-2} \cdot A^{-1}}\) |
| magnetic moment | weber metre | \(\mathrm{Wb \cdot m}\) | \(\mathrm{m^{3} \cdot kg \cdot s^{-2} \cdot A^{-1}}\) |
| magnetic rigidity | tesla metre | \(\mathrm{T \cdot m}\) | \(\mathrm{m \cdot kg \cdot s^{-2} \cdot A^{-1}}\) |
| magnetomotive force | ampere radian | \(\mathrm{A \cdot rad}\) | \(\mathrm{A}\) |
| magnetic susceptibility | metre per henry | \(\mathrm{m/H}\) | \(\mathrm{m^{-1} \cdot kg^{-1} \cdot s^{2} \cdot A^{2}}\) |
Photometry
| Quantity | Name | Symbol | SI Equivalents |
|---|---|---|---|
| luminous energy | lumen second | \(\mathrm{lm \cdot s}\) | \(\mathrm{s \cdot cd}\) |
| luminous exposure | lux second | \(\mathrm{lx \cdot s}\) | \(\mathrm{m^{-2} \cdot s \cdot cd}\) |
| luminance | candela per square metre | \(\mathrm{cd/m^{2}}\) | \(\mathrm{m^{-2} \cdot cd}\) |
| luminous efficacy | lumen per watt | \(\mathrm{lm / W}\) | \(\mathrm{m^{-2} \cdot kg^{-1} \cdot s^{3} \cdot cd}\) |
Optics
| Quantity | Name | Symbol | SI Equivalents |
|---|---|---|---|
| optical power | diopter | \(D\) | \(\mathrm{m^{-1}}\) |
Thermodynamics
| Quantity | Name | Symbol | SI Equivalents |
|---|---|---|---|
| heat capacity, entropy | joule per kilogram | \(\mathrm{J/kg}\) | \(\mathrm{m^{2} \cdot s^{-2}}\) |
| heating value (energy value, calorific value) |
joule per kilogram, joule per cubic metre, joule per mole |
\(\mathrm{J/kg}\) \(\mathrm{J/m^{3}}\) \(\mathrm{J/mol}\) |
\(\mathrm{m^{2} \cdot s^{-2}}\) \(\mathrm{kg \cdot m^{-1} \cdot s^{-2}}\) \(\mathrm{kg \cdot m^{2} \cdot mol^{-1} \cdot s^{-2}}\) |
| specific heat capacity, specific entropy | joule per kilogram kelvin | \(\mathrm{J/\left( K \cdot kg \right)}\) | \(\mathrm{m^{2} \cdot s^{-2} \cdot K^{-1}}\) |
| thermal conductivity | watt per metre kelvin | \(\mathrm{W/\left( m \cdot K \right)}\) | \(\mathrm{kg \cdot m \cdot s^{-3} \cdot K^{-1}}\) |
| thermal resistance | kelvin per watt | \(\mathrm{K/W}\) | \(\mathrm{s^{3} \cdot K \cdot kg^{-1} \cdot m^{-2}}\) |
| thermal expansion coefficient | reciprocal kelvin | \(\mathrm{K^{-1}}\) | \(\mathrm{K^{-1}}\) |
| temperature gradient | kelvin per metre | \(\mathrm{K/m}\) | \(\mathrm{K \cdot m^{-1}}\) |