Home Handbook Мерки и теглилки International System of Units - SI (Supplementary Units)
Български (България)English (United Kingdom)
International System of Units - SI (Supplementary Units)

Международна система за мерки - СИ


  • Unit of plane angle : radian ( rad)
    The radian is the plane angle formed by two radius which cut an arc of circle having the same length of the radius.
  • Unit of solid angle : steradian (sr)
    The steradian is the solid angle, with the vertex at the centre of a sphere, which defines an area equal to the square of the radius on the surface of the sphere.


Physical quantity
NameSymbol In other SI unitsIn SI basic units
FrequencyhertzHz s-1
ForcenewtonN m·kg·s-2
Pressure and tensionpascal PaN·m²m-1·kg·s-2
Energy, work, heat quantityjouleJN·mm²·kg·s-2
Power (mechanical, thermal, electric)wattWJ·s-1m²·kg·s-3
Quantity of electricity, electric charge coulombC A·s
Voltage, electric potentialvoltVW·A-1m²·kg·s-3·A-1
Electric resistanceohmΩV·A-1m²·kg·s-3·A-2
Electric conductanceSiemensSA·V-1m-2·kg-1·s³·A²
Electric capacitancefaradFC·V-1m²·kg-1·s4·A²
Magnetic fluxweberWbV·sm²·kg·s-2·A-1
Magnetic inductionteslaTWb·m-2kg·s-2·A-1
Electric inductancehenryHWb·A-1m²·kg·s-2·A-2
Luminous fluxlumenlm cd·sr
ActivitybecquerelBq s-1
Absorbed dosegrayGyJ·kg-1m²·s-2