Environmental Engineering Reference
In-Depth Information
TABLE A.1
SI Units
SI Base Unit Value
a
Measurement
Unit
Symbol
Base units
Length
meter
m
m
Mass
kilogram
kg
kg
Time
second
s
s
Electric current
ampere
A
A
Thermodynamic temperature
kelvin
K
K
Amount of substance
mole
mol
mol
Derived units
Plane angle
radian
rad
1
Solid angle
stearadian
st
1
Frequency
hertz
Hz
1/s
kg m/s
2
Force
newton
N
N/m
2
kg/m s
2
Pressure
pascal
Pa
=
Nm
=
kg m
2
/s
2
Energy
joule
J
J/s
=
kg m
2
/s
3
Power
watt
W
Electric charge
coulomb
C
A s
W/A
=
kg m
2
/A s
3
Electric potential
volt
V
C/V
=
A
2
s
4
/kg m
2
Electric capacitance
farad
F
V/A
=
m
2
kg/A
2
s
3
Electric resistance
ohm
V s
=
kg m
2
/A s
2
Magnetic flux
weber
Wb
Wb/m
2
=
kg/A s
2
Magnetic flux density
tesla
T
Wb/A
=
kg m
2
/A
2
s
2
Inductance
henry
H
Activity (radionuclide)
becquerel
Bq
1/s
J/kg
=
m
2
/s
2
Absorbed dose
gray
Gy
J/kg
=
m
2
/s
2
Dose equivalent
sievert
Sv
Defined units
a
Plane angle
◦
degree (angular)
(
π/
180
) rad
Length
nautical mile
nmile
1852
m
Speed
knot (nmile/h)
kt
0.51444
m/s
10
4
m
2
Area
hectare
ha
3)
m
3
Volume
liter
L
1E(
−
Mass
ton (metric)
ton
1E(3)
kg
Pressure
bar
bar
1E(5)
Pa
Time
minute
min
60
s
Time
hour
h
60
min
=
3600
s
Time
day
d
24
h
=
86400
s
Time
year (365 days)
y
3.1536 E(7)
s
◦
C
Temperature
centigrade
K
Activity (radionuclide)
curie
Ci
3.7E(10)
Bq
Absorbed dose
rad
rd
1E(
−
2)
Gy
Dose equivalent
rem
rem
1E(
−
2)
Sv
Energy
calorie (Int. table)
cal
IT
4.1868
J
a
Boldface values are exact.
