SI Units and the British Units

Length

1 m = 3.281 ft
1 km = 0.621 mile

1 ft = 0.3048 m
1 mile = 1.609 km

Speed

1 m/s = 3.281 ft/s
1 km/h = 0.621 mph

1 ft/s = 0.305 m/s
1 mph = 1.61 km/h

Acceleration

1 m/s² = 3.281 ft/s²

1 ft/s² = 0.305 m/s²

Mass

1 kg = 2.205 lb

1 lb = 0.454 kg

Force

1 N = 0.225 lbf

1 lbf = 4.448 N

Torque

1 Nm = 0.738 lbf·ft

1 lbf·ft = 1.355 Nm

Pressure

1 N/m² = 0.000145 lbf/in²
1 bar = 14.5038 lbf/in²

1 lbf/in² = 6896 N/m²

Energy / Work

1 J = 0.738 ft·lbf
1 J = 0.239 cal
1 kJ = 0.948 BTU

1 ft·lbf = 1.355 J
1 cal = 4.186 J
1 BTU = 1.055 kJ

Power

1 kW = 1.34 hp

1 hp = 0.7457 kW

Fuel Consumption

1 km/L = 2.82 mpg

1 mpg = 0.354 km/L

Specific Fuel Consumption

1 kg/kWh = 1.65 lb/bhp·h

1 lb/bhp·h = 0.606 kg/kWh

Calorific Value

1 kJ/kg = 0.43 BTU/lb

1 BTU/lb = 2.326 kJ/kg