Appendix V: Units

Following the International System of Units (SI, abbreviated from the French Système international (d'unités))

Unit name Unit symbol Quantity name
metre m length
kilogram kg mass
second s time
ampere A electric current
kelvin K thermodynamic temperature
mole mol amount of substance
candela cd luminous intensity
radian rad angle
steradian sr solid angle
hertz Hz frequency
newton N force, weight
pascal Pa pressure, stress
joule J energy, work, heat
watt W power, radiant flux
coulomb C electric charge or quantity of electricity
volt V voltage (electrical potential), emf
farad F capacitance
ohm resistance, impedance, reactance
siemens S electrical conductance
weber Wb magnetic flux
tesla T magnetic flux density
henry H inductance
degree Celsius °C temperature relative to 273.15 K
lumen lm luminous flux
lux lx illuminance
becquerel Bq radioactivity (decays per unit time)
gray Gy absorbed dose (of ionizing radiation)
sievert Sv equivalent dose (of ionizing radiation)
katal kat catalytic activity



Prefix name Prefix symbol Factor
deca da 101
hecto h 102
kilo k 103
mega M 106
giga G 109
tera T 1012
peta P 1015
exa E 1018
zetta Z 1021
yotta Y 1024


Prefix name Prefix symbol Factor
deci d 10-1
centi c 10-2
milli m 10-3
micro µ 10-6
nano n 10-9
pico p 10-12
femto f 10-15
atto a 10-18
zepto z 10-21
yocto y 10-24