Omron CS1W-FLN22 Operation Manual page 272

International System of Units
SI Supplementary Units
Quantity Unit name
Plane angle Radian
Solid angle Steradian
SI Derived Units
Quantity Unit name
Plane angle radian
Solid angle steradian
Frequency hertz
Force newton
Pressure, stress pascal
Energy, work, quan- joule
tity of heat
Power, radiant flux watt
Electric charge, coulomh
quantity of electricity
Electric potential, volt
electromotive force
Electric capacitance farad
Electrical resistance ohm
Electric conductance siemens
Magnetic flux weber
Magnetic flux density tesla
Inductance henry
Temperature degree Celsius
Luminous flux lumen
Illuminance lux
To indicate decimal multiples or submultiples of these units, the following list of prefixes was established. For
example, the hectopascal (hPa), a unit commonly heard in weather forecasts, is one pascal (Pa) multiplied by
2
10 , which is indicated by adding the prefix hecto (h). The current SI units specify 20 prefixes from 10
-24
10 . For practical purposes, these units are also used in combination with time units (minute, hour, and sec-
ond), angle units (degree, minute, second), volume units (liter), and mass units (ton).
SI Unit Prefixes
Multiple
Symbol
−24
y
10
−21
z
10
−18
a
10
−15
f
10
−12
p
10
246
Unit
symbol
rad A radian is the plane angle between two radii of a circle that cuts
off on the circumference an arc equal in length to the radius.
sr A steradian is the solid angle that, having its vertex in the center of
a sphere, cuts off an area of the surface of the sphere equal to that
of a square with sides equal in length to the radius of the sphere.
Unit Expressed in terms of other
symbol
rad ---
sr ---
Hz
1 Hz = 1 s
N
1 N = 1 kg·m·s
Pa
1 Pa = 1 N·m
J 1 J = 1 N·m
W
1 W = 1 J·s
C 1 C = 1 A·s
V
1 V = 1 W·A
F
1 F = 1 C·V
Ω
1 Ω = 1 V·A
S
1 S = 1 A·V
wb 1 wb = 1 V·s
T
1 T = 1 wb·m
H
1 H = 1 wb·A
°C
t°C = (t + 273.15) K
lm 1 lm = 1 cd·sr
lx
1 lx = 1 cd·s·rm
Prefix
Name
yocto
septo
atto
femto
pico
Definition
SI units
−1
−2
−2
−1
−1
−1
−1
−1
−2
−1
−2
Appendix G
24
to