## Conversion Factors to SI Units

Google is great for converting units. For example, to convert 10 feet to meters, type "10 ft in m" into google.

Acceleration

1 ft/s2 = 0.3048 m/s2
g = 9.807 m/s2
Area
1 acre = 9.807 m/s2
1 ft2 = 9.290 x 10-2 m2
1 in2 = 6.45 x 10-4 m2
1 mi2 = 2.59 x 106 m2
Density
1 g/cm3 = 103 kg/m3
Energy
1 Btu = 1054 J
1 calorie (cal) = 4.184 J
1 electron volt (eV) = 1.602 x 10-19 J
1 foot pound (ftlb) = 1.356 J
1 kilowatt hour (kWh) = 3.60 x 106 J
Force
1 dyne = 10-5 N
1 lb = 4.448 N
Length
1 angstrom (Å) = 10-10 m
1 ft = 0.3048 m
1 in = 2.54 x 10-2 m
1 light year = 9.461 x 1015 m
1 mile = 1609 m
Mass
1 atomic mass unit (u) = 1.60606 x 10-27 kg
1 gram = 10-3 kg
Power
1 Btu = 1054 W
1 cal/s = 4.184 W
1 ftlb/s = 1.356 W
1 horsepower (hp) = 746 W
Pressure
1 atmosphere (atm) = 1.013 x 105 pascal (Pa)
1 bar = 105 Pa
1 cmHg = 1333 Pa
1 lb/ft2 = 47.88 Pa
1 lb/in2 (psi) = 6895 Pa
1 N/m2 = 1 pascal (Pa)
1 torr = 133.3 Pa
Speed
1 ft/s (fps) = 0.3048 m/s
1 km/h = 0.2778 m/s
1 mi/hr (mph) = 0.44704 m/s
Temperature
TKelvin = TCelsius = 273.15
TKelvin = (9/5)*( TFahrenheit + 459.67 )
TCelsius = (5/9)*( TFahrenheit - 32)
TKelvin = (5/9)*TRankine
Time
1 day = 86400 s
1 year = 3.16 x 107 s
Volume
1 ft3 = 2.832 x 10-2 m3
1 gallon = 3.785 x 10-5 m3
1 in3 = 1.639 x 10 -5 m3
1 liter = 10-3 m