Maths
SI Units

SI Base Units
SI Derived Units
SI Derived Units With Special Names
SI Derived Units Expressed by Means of Special Names
SI Supplementary Units
SI Derived Units Formed Using Supplementary Units

SI Base Units
QuantityNameSymbol
Lengthmetrem
Masskilogramkg
Timeseconds
Electric CurrentampereA
Thermodynamic TemperaturekelvinK
Amount of Substancemolemol
Luminous Intensitycandelacd

SI Derived Units
QuantityNameSymbol
Areasquare metrem2
Volumecubic metrem3
Speed / Velocitymetre per secondm/s
Accelerationmetre per second squaredm/s2
Wave Numberreciprocal metrem-1
Density / Mass Densitykilogram per cubic metrekg/m3
Specific Volumecubic metre per kilogramm3/kg
Current Densityampere per square metreA/m2
Magnetic Field Strengthampere per metreA/m
Concentrationmole per cubic metremol/m3
Luminancecandela per square metrecd/m2

SI Derived Units With Special Names
QuantityNameSymbolExpression in terms of other unitsExpression in terms of SI base units
FrequencyhertzHzs-1
ForcenewtonNm kg s-2
Pressure / StresspascalPaN/m2m-1 kg s-2
Energy / Work / Quantity of HeatjouleJN mm2 kg s-2
Power / Radiant FluxwattWJ/sm2 kg s-3
Electric Charge / Quantity of ElectricitycoulombCs A
Electric Potential / Potential Difference / Electromotive ForcevoltVW/Am2 kg s-3 A-1
CapacitancefaradFC/Vm-2 kg-1 s4 A2
Electric ResistanceohmohmV/Am2 kg s-2 A-1
Electric ConductancesiemensSA/Vm-2 kg-1 s3 A2
Magnetic FluxweberWbV sm2 kg s-2 A-1
Magnetic Flux DensityteslaTWb/m2kg s-2 A-1
InductancehenryHWb/AM2 kg s-2 A-2
Celsius Temperaturedegree celsius°CK
Luminous Fluxlumenlmcd sr
Illuminanceluxlxlm/m2m-2 cd sr
Activity of a RadionuclidebequerelBqs-1
Absorbed Dose / Specific Energy Imparted / Kerma / Absorbed Dose IndexgrayGyJ/kgm2 s-2
Dose Equivalent / Dose Equivalent IndexsievertSvJ/kgm2 s-2

SI Derived Units Expressed by Means of Special Names
QuantityNameSymbolExpression in terms of SI base units
Dynamic Viscositypascal secondPa sm-1 kg s-1
Moment of Forcenewton meterN mM2 kg s-2
Surface Tensionnewton per metreN/mkg s-2
Heat Flux Density / Irradiancewatt per square metreW/m2kg s-3
Heat Capacity / Entropyjoule per kelvinJ/KM2 kg s-2 K-1
Specific Heat Capacity / Specific Entropyjoule per kilogram kelvinJ/(kg K)m2 s-2 K-1
Specific Energyjoule per kilogramJ/kgM2 s-2
Thermal Conductivitywatt per metre kelvinW/(m K)m kg s-3 K-1
Energy Densityjoule per cubic metreJ/m3m-1 kg s-2
Electric Field Strengthvolt per metreV/mm kg s-3 A-1
Electric Charge Densitycoulomb per cubic metreC/m3m-3 s A
Electric Flux Densitycoulomb per square metreC/m2m-2 s A
Permittivityfarad per metreF/mm-3 kg-1 s4 A2
Permeabilityhenry per metreH/mm kg s-2 A-2
Molar Energyjoule per moleJ/molm2 kg s-2 mol-1
Molar Entropy / Molar Heat Capacityjoule per mole kelvinJ/(mol K)m2 kg s-2 K-1 mol-1
Exposure (x and gamma rays)coulomb per kilogramC/kgkg-1 s A
Absorbed Dose Rategray per secondGy/sM2 s-3

SI Supplementary Units
QuantityNameSymbolExpression in terms of SI base units
Plane Angleradianradm m-1 = 1
Solid Anglesteradiansrm2 m-2 = 1

SI Derived Units Formed Using Supplementary Units
QuantityNameSymbol
Angular Velocityradian per secondrad/s
Angular Accelerationradian per second squaredrad/s2
Radiant Intensitywatt per steradianW/sr
Radiancewatt per square metre steradianW/(m2 sr)



Page compiled: Wed Sep 05 18:37:57 GMT+01:00 2001