Speaking in technically words **torque** is a force that causes something to spin around a central point such as an axle.

Referring to the rotating axle, **torque**, also called rotary force, is the product of the force multiplied by the length of the lever arm.

The formula is:

*M = F x I*

where

is the torque measured in "newton-metre" (Nm)*M*is a force measured in "newton" (N)*F*is the length of the lever arm measured in "metre" (m)*I*

Useful formula for relationship between torque and power:

where

is measured in "kilowatt" (kW)*Power*is measured in "newton-metre" (Nm)*Torque*in measured in "revolutions per minute" (rpm)*Rotational speed*- 6,000 comes from 60 seconds per minute times 1000 watts per kilowatt

Some people (e.g. American automotive engineers) use **horsepower** (imperial mechanical) for power, foot-pounds (lbf·ft) for torque and rpm (revolutions per minute) for angular speed. This results in the formula changing to:
This conversion factor is approximate because the transcendental number p appears in it.

^ top