10.3 Conversion tables
Table 10.4: SI units of calculation (selection) (Source: OEKOTOP, compiled from various
sources)
Quantity
Length
Area
Volume
Mass
Density
Force, load
Stress
Pressure
Energy
Work
Quantity of heat
Power
Temperature
Velocity
Acceleration
Symbol
1
A
V
M
D
F
d
p
E
W
Q
P
t
v
b
Unit
m
m³
m³
t; kg
t/m³
kN
MN/m²
MN/m²
kWh
kNm
kWh
kW
°C, K
m/s
m/s
Conversion
1 m = 10 dm = 100 cm = 1000 mm
1 m³ = 100 dm³ = 10000 cm³
1 m³ = 1000 dm³ = 1 mill. cm³
1 t = 1000 kg
1 t/m³ = 1 kg/dm³
1 kN= 1000 N ~100 kp
1 MN/m² = 1 N/mm² ~10 kp/cm²
1 MN/m² = 1 MPa ~10 kp/cm²
1 kWh = 3.6 • 106 Ws ~3.6 • 105 kpm
1 J = 1 Ws = 1 Nm 1 kNm ~ 100 kpm
1 kWh = 3.6 X 106 Ws; 1 kcal = 4187 Ws
1 kW ~100 kpm/s = 1.36 PS
0ºK = -273 °C; 0ºC = 273 °K
1 m/s= 3.6 km/in
1 m/s², acceleration due to gravity: 9.81 m/s²
Table 10.5: Conversion of imperial measures (Source: Sasse, 1984)
Length
Area
Volume
Mass
Pressure
Quantity
of heat
Power
1 m = 1.094 yrd
1 cm = 0.0328 ft
1 cm = 0.394 inch
1 m² = 10.76 sqft
1 cm² = 0.155 sq.in
1 ha = 2.47 acre
1 1 = 0.220 gall.
1 m³ = 35.32 cbft
1 kg = 2.205 lb
1 MN/m² = 2.05 lb/sqft
1 cm Ws = 205 lb/sqft
1 kcal = 3.969 BTU
1 kWh = 3413.3 BTU
1 kcal/kg = 1799 BTU/lb
1 PS = 0.986 HP
1 kpm/s = 7.24 ft.lb/s
1 yrd = 0.914 m
1 ft = 30.5 cm
1 inch = 2.54 cm
1 sqft = 0.092 m²
1 sq.in = 6.452 cm²
1 acre = 0.405 ha
1 gall. = 4.55 1
1 cbft = 28.31
1 lb = 0.454 kg
1 lb/sqft = 0.488 MN/m²
1 lb/sqft = 70.3 cm Ws
1 BTU = 0.252 kcal
1000 BTU = 0.293 kcal
1 BTU/lb = 0.556 kcal/kg
1 HP = 1.014 PS
1 ft.lb/s = 0.138 kpm/s
Table 10.6: Conversion factors for work, energy and power (Source: Wendehorst, 1978)
Comparison of work units (work = power X time)
1 kpm =
1 PSh*=
1 Ws = J =
1 kWh =
kpm
1
270 X 103
0.102
367.1 X 103
PSh*
3.70 X 10-6
1
377.7 X 10-9
1.36
Ws = J
9.807
2.648 X 106
1
3.6 X 106
kWh
2.7 X 10-6
0.7355
277.8 X 10-9
1
kcal
2.342 X 10-3
632.4
239 X 10-6
860
120