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Table 1. SI base units 



Table 2. Examples of SI derived units 

SI derived unit 

Derived quantity  Name  Symbol 

area  square meter  m^{2} 
volume  cubic meter  m^{3} 
speed, velocity  meter per second  m/s 
acceleration  meter per second squared  m/s^{2} 
wave number  reciprocal meter  m^{1} 
mass density  kilogram per cubic meter  kg/m^{3} 
specific volume  cubic meter per kilogram  m^{3}/kg 
current density  ampere per square meter  A/m^{2} 
magnetic field strength  ampere per meter  A/m 
amountofsubstance concentration  mole per cubic meter  mol/m^{3} 
luminance  candela per square meter  cd/m^{2} 
mass fraction  kilogram per kilogram, which may be represented by the number 1  kg/kg = 1 
Table 3. SI derived units with special names and symbols 

SI derived unit 

Derived quantity  Name  Symbol  Expression in terms of other SI units 
Expression in terms of SI base units 

plane angle  radian ^{(a)}  rad    m·m^{1 }= 1 ^{(b)} 
solid angle  steradian ^{(a)}  sr ^{(c)}    m^{2}·m^{2 }= 1 ^{(b)} 
frequency  hertz  Hz    s^{1} 
force  newton  N    m·kg·s^{2} 
pressure, stress  pascal  Pa  N/m^{2}  m^{1}·kg·s^{2} 
energy, work, quantity of heat  joule  J  N·m  m^{2}·kg·s^{2} 
power, radiant flux  watt  W  J/s  m^{2}·kg·s^{3} 
electric charge, quantity of electricity  coulomb  C    s·A 
electric potential difference, electromotive force 
volt  V  W/A  m^{2}·kg·s^{3}·A^{1} 
capacitance  farad  F  C/V  m^{2}·kg^{1}·s^{4}·A^{2} 
electric resistance  ohm  V/A  m^{2}·kg·s^{3}·A^{2}  
electric conductance  siemens  S  A/V  m^{2}·kg^{1}·s^{3}·A^{2} 
magnetic flux  weber  Wb  V·s  m^{2}·kg·s^{2}·A^{1} 
magnetic flux density  tesla  T  Wb/m^{2}  kg·s^{2}·A^{1} 
inductance  henry  H  Wb/A  m^{2}·kg·s^{2}·A^{2} 
Celsius temperature  degree Celsius  °C    K 
luminous flux  lumen  lm  cd·sr ^{(c)}  m^{2}·m^{2}·cd = cd 
illuminance  lux  lx  lm/m^{2}  m^{2}·m^{4}·cd = m^{2}·cd 
activity (of a radionuclide)  becquerel  Bq    s^{1} 
absorbed dose, specific energy (imparted), kerma  gray  Gy  J/kg  m^{2}·s^{2} 
dose equivalent ^{(d)}  sievert  Sv  J/kg  m^{2}·s^{2} 
catalytic activity  katal  kat  s^{1}·mol  
^{(a)} The radian and steradian may be used advantageously in expressions for derived
units to distinguish between quantities of a different nature but of the same dimension; some examples are
given in Table 4. ^{(b)} In practice, the symbols rad and sr are used where appropriate, but the derived unit "1" is generally omitted. ^{(c)} In photometry, the unit name steradian and the unit symbol sr are usually retained in expressions for derived units. ^{(d)} Other quantities expressed in sieverts are ambient dose equivalent, directional dose equivalent, personal dose equivalent, and organ equivalent dose. 

Table 4. Examples of SI derived units whose names and symbols include SI derived units with special names and symbols 

SI derived unit 

Derived quantity  Name  Symbol 

dynamic viscosity  pascal second  Pa·s 
moment of force  newton meter  N·m 
surface tension  newton per meter  N/m 
angular velocity  radian per second  rad/s 
angular acceleration  radian per second squared  rad/s^{2} 
heat flux density, irradiance  watt per square meter  W/m^{2} 
heat capacity, entropy  joule per kelvin  J/K 
specific heat capacity, specific entropy  joule per kilogram kelvin  J/(kg·K) 
specific energy  joule per kilogram  J/kg 
thermal conductivity  watt per meter kelvin  W/(m·K) 
energy density  joule per cubic meter  J/m^{3} 
electric field strength  volt per meter  V/m 
electric charge density  coulomb per cubic meter  C/m^{3} 
electric flux density  coulomb per square meter  C/m^{2} 
permittivity  farad per meter  F/m 
permeability  henry per meter  H/m 
molar energy  joule per mole  J/mol 
molar entropy, molar heat capacity  joule per mole kelvin  J/(mol·K) 
exposure (x and rays)  coulomb per kilogram  C/kg 
absorbed dose rate  gray per second  Gy/s 
radiant intensity  watt per steradian  W/sr 
radiance  watt per square meter steradian  W/(m^{2}·sr) 
catalytic (activity) concentration  katal per cubic meter  kat/m^{3} 