Base units
Time t
second: s – The base unit of time in the International Systems of Units.
Length L
meter: m – The base unit of length in the International Systems of Units.
angstrom (ångström): Å – A metric unit of length, equal to 10-10 m. Not that it is not part of the SI system of units, but it can be considered as part of the metric system in general.
Mass m
kilogram: kg – The base unit of mass in the International Systems of Units.
Electric current
ampere: A – The base unit of electric current in the International Systems of Units.
Thermodynamic temperature
kelvin: K – The base unit of thermodynamic temperature in the International Systems of Units.
Amount of substance
mole: mol – The base unit of amount of substance in the International Systems of Units.
Luminous intensity
candela: cd– The base unit of luminous intensity in the International Systems of Units.
Magnetism
Magnetic moment m (vector)
ampere meter squared: A · m2
electromagnetic unit: emu – Note that emu is not a unit. However, it is sometimes used to describe the strength of a magnetic moment and has the value of 10-3 A · m2. For example, some vibrating sample magnetometers (VSM) use this unit.
Magnetic field strength H
ampere per meter: A/m
Magnetic flux
Weber: Wb – The weber is a derived unit of the magnetic flux in the International System of Units. This unit is named in honor of Wilhelm Eduard Weber.
1 Wb = 1 V · s = 1 T · m2 = 1 Ω · C = 1 H · A = 1 J/A = 1 (kg · m2 )/( s2 · A) = 1 · 108 Mx
Magnetic flux density or magnetic induction B
Tesla: T – The tesla is a derived unit of the magnetic induction in the International System of Units. This unit is named in honor of Nikola Tesla.
1 T = 1 kg/( A · s2) = 1 N/(A · m) = 1 (V · s)/m2 = 1 J/ (A · m2) = 1 (H ·A)/ m2 = 1 Wb/m2 = 1 kg/(C · s) = 1 (N · s)/(C · m)
in vacuum B = μ0 · H