Useful Unit Convertions

Quantity

English

SI

Velocity

1 mph; 1 knot

0.45 m/s; 0.514 m/s

Temperature

°F

(°F - 32)(5/9) = °C

Length

39.4 in

1 m

Pressure

1 psi

6895 Pa

Mass

1 lb

0.45 kg

Energy

1 ft lb

1.36 J

Volume

1 gal

3.8 x 10-3 m3


Standard Atmosphere

1 atm

1013.25 mb; 760 mmHg; 29.921 inHg; 14.7 lb in-2


Other Units

Quantity

Name of unit

Symbol

Fundamental Units

Volume
liter
l

10-3 m3
Pressure
millibar

mbar or mb

102 Pa