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Quantities, units and symbols

The following table shows the units and symbols for a series of quantities that you will meet in Physics. Sometimes the symbol for the quantity is given and sometimes the symbol for the unit which ever is the more appropriate.

Quantity Unit Symbol
activity (of a radioactive source) becquerel Bq
amount of substance mole mol
angular momentum Js L
atomic mass atomic mass unit u
capacitance farad (F) C
current density Am-1 j
electric charge coulomb C
electric potential difference volt V
electromotive force volt V
electric conductance siemens S
electric capacitance farad F
electric current ampere A
electric potential difference volt V
electric field strength NC-1 or Vm-1 S
electric resistance ohm Ω
electrical conductivity Sm-1 σ
electrical resistivity Ωm ρ
force newton N
frequency hertz Hz
gravitational constant Nm2kg-2 G
gravitational field strength Nkg-1 g
gravitational potential Jkg-1 V
inductance (L) henry H
length metre m
luminance lux lx
luminous flux lumen lm
luminous intensity candela cd
magnetic flux density tesla T
magnetic flux (magnetic induction) weber W
mass kilogram kg
moment of a force (torque) Nm M
moment of inertia kgm2 I
momentum Ns P
permeability Hm-1 μ
permittivity Fm-1 ε
power watt W
presure and stress pascal Pa
specific heat capacity Jkg-1K-1 c
specific latent heat Jkg-1 L
surface tension Nm-1 s
thermal conductivity Wm-1K-1 k
thermodynamic temperature kelvin K
time (t) second> s
viscosity Ns-2 h
work, energy, heat joule J
Young modulus Pa E

© Keith Gibbs