List of common physics notations
This is a list of common physical constants and variables, and their notations. Note that bold text indicates that the quantity is a vector.
Latin characters
| Symbol | Meaning | SI unit of measure |
| magnetic vector potential | tesla meter | |
| area | square meters | |
| amplitude | meter | |
| atomic mass number | unitless | |
| acceleration | meters per second squared | |
| magnetic flux density also called the magnetic field density or magnetic induction | tesla, or equivalently, weber per square meter | |
| capacitance | farad | |
| heat capacity | joule per kelvin | |
| constant of integration | varied depending on context | |
| speed of light | 299,792,458 meter per second | |
| speed of sound | 340.29 meter per second | |
| specific heat capacity | joule per kilogram per kelvin | |
| viscous damping coefficient | kilogram per second | |
| electric displacement field also called the electric flux density | coulomb per square meter | |
| density | kilograms per cubic meter | |
| distance | meter | |
| direction | unitless | |
| impact parameter | meter | |
| diameter | meter | |
| differential | ||
| differential vector element of surface area A, with infinitesimally small magnitude and direction normal to surface S | square meter | |
| differential element of volume V enclosed by surface S | cubic meter | |
| electric field | newton per coulomb, or equivalently, volt per meter | |
| energy | joule | |
| Young's Modulus | pascal or newton per square meter | |
| eccentricity | unitless | |
| 2.71828... | unitless | |
| electron | unitless | |
| elementary charge | coulomb | |
| force | newton | |
| Faraday constant | coulombs per mole | |
| frequency | hertz | |
| function | ||
| friction | newton | |
| electrical conductance | siemens | |
| gravitational constant | newton meter squared per kilogram squared | |
| acceleration due to gravity | meters per second squared, or equivalently, newtons per kilogram | |
| magnetic field strength | ampere per meter | |
| Hamiltonian | joule | |
| height | meter | |
| Planck constant | joule second | |
| reduced Planck constant | joule second | |
| action | joule second | |
| intensity | watt per square meter | |
| sound intensity | watt per square meter | |
| electric current | ampere | |
| moment of inertia | kilogram meter squared | |
| intensity | watt per square meter | |
| imaginary unit | unitless | |
| Cartesian x-axis basis unit vector | unitless | |
| current density | ampere per square meter | |
| impulse | kilogram meter per second | |
| jerk | meters per second cubed | |
| imaginary unit | unitless | |
| Cartesian y-axis basis unit vector | unitless | |
| kinetic energy | joule | |
| Boltzmann constant | joule per kelvin | |
| wavenumber, wave vector | radians per meter | |
| stiffness | newtons per meter | |
| Cartesian z-axis basis unit vector | unitless | |
| inductance | henry | |
| luminosity | watt | |
| angular momentum | newton meter second | |
| Lagrangian | joule | |
| length | meter | |
| ℓ | azimuthal quantum number | unitless |
| magnetization | amperes per meter | |
| moment of force often simply called moment or torque | newton meter | |
| mass | kilogram | |
| normal vector | unit varies depending on context | |
| atomic number | unitless | |
| refractive index | unitless | |
| principal quantum number | unitless | |
| amount of substance | mole | |
| power | watt | |
| probability | unitless | |
| momentum | kilogram meter per second | |
| pressure | pascal | |
| electric charge | coulomb | |
| Heat | joule | |
| electric charge | coulomb | |
| electrical resistance | ohm | |
| Ricci tensor | reciprocal square meter | |
| radiancy | meter per second | |
| gas constant | joule per mole per kelvin | |
| radius vector | meter | |
| radius or distance | meter | |
| surface area | m2 | |
| entropy | joule per kelvin | |
| action | joule second | |
| displacement | meter | |
| arc length | meter | |
| period | second | |
| temperature | kelvin or Celsius | |
| time | second | |
| four-velocity | meter per second | |
| potential energy | joule | |
| internal energy | joule | |
| relativistic mass | kilogram | |
| energy density | joule per cubic meter or joule per kilogram depending on the context | |
| voltage also called electric potential difference | volt | |
| volume | cubic meter | |
| shear force | ||
| velocity | meter per second | |
| mechanical work | joule | |
| width | meter | |
| position vector | meter | |
| displacement | meter | |
| a generic unknown | varied depending on context | |
| electrical impedance | ohm |
Greek characters
| Symbol | Name | Meaning | SI unit of measure |
| alpha | alpha particle | ||
| alpha | angular acceleration | radian per second squared | |
| alpha | fine-structure constant | unitless | |
| beta | velocity in terms of the speed of light c | unitless | |
| beta | beta particle | ||
| gamma | Lorentz factor | unitless | |
| gamma | photon | ||
| gamma | gamma ray | ||
| gamma | shear strain | ||
| gamma | heat capacity ratio | unitless | |
| delta | change in a variable | unitless | |
| delta | Laplace operator | per square meter | |
| delta | displacement | meter | |
| delta | Dirac delta function | ||
| epsilon | permittivity | farad per meter | |
| epsilon | strain | unitless | |
| epsilon nought | vacuum permittivity constant | farad per meter | |
| zeta | damping ratio | unitless | |
| eta | energy efficiency | unitless | |
| eta | coefficient of viscosity also called simply viscosity | pascal second | |
| eta | jerk | meter per second cubed | |
| theta | angular displacement | radian | |
| kappa | torsion coefficient also called torsion constant | newton meter per radian | |
| lambda | cosmological constant | per second squared | |
| lambda | wavelength | meter | |
| lambda | linear charge density | coulomb per meter | |
| lambda | eigenvalue | non-zero vector | |
| mu | magnetic moment | ampere square meter | |
| mu | coefficient of friction | unitless | |
| mu | dynamic viscosity | pascal second | |
| mu | permeability | henry per meter | |
| mu | reduced mass | kilogram | |
| mu | gravitational parameter | ||
| mu nought | vacuum permeability constant or magnetic constant | henry per meter | |
| nu | frequency | hertz | |
| nu | kinematic viscosity | meters squared per second | |
| nu | neutrino | ||
| pi | 3.14159... | unitless | |
| rho | mass density usually simply called density | kilogram per cubic meter | |
| rho | volume charge density | coulomb per cubic meter | |
| rho | resistivity | ohm meter | |
| sigma | summation operator | ||
| sigma | area charge density | coulomb per square meter | |
| sigma | electrical conductivity | siemens per meter | |
| sigma | normal stress | pascal | |
| sigma | scattering cross section | barn | |
| tau | torque | newton meter | |
| tau | shear stress | pascal | |
| tau | time constant | second | |
| tau | 6.28318... | unitless | |
| phi | field strength | unit varies depending on context | |
| phi | magnetic flux | weber | |
| phi | electric potential | volt | |
| phi | Higgs field work function | ||
| psi | wave function | m−3/2 | |
| omega | electric resistance | ohm | |
| omega | angular frequency | radian per second |