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Table II. Derived units with assigned names

Symbo
Quantity Unit Equals Definition / Note
l

Space and time:

The plain angle

which, when
centered in a circle,

Plane angle radian rad cuts off an arc
whose length is
equal to the circle

radius.

The solid angle

which, when
centered in a sphere,

Solid angle steradian sr cuts off a cap whose
surface equals that
of a square having
the radius as side.

-1

Frequency hertz Hz 1 s [number of events or

cycles]/[time].
Mechanics:
-
1 kg.m.s [mass].[acceleration]

Force newton N 2
.
-2 [force]/[area]. Also:
Pressure pascal Pa 1 N.m
stress.

[force].[length].
Energy joule J 1 N.m
Also: Work, Heat

[energy]/[time].

-1

Power watt W 1 J.s
Also: Radiant flux
Thermodynamics:
o
T [ C] = T [K] -
o

Temperature celsius C 1 K
273.15
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