Pound-foot (torque)

A pound-foot, abbreviated from pound-force foot, is a unit of torque representing one pound of force acting at a perpendicular distance of one foot from a pivot point. Conversely one foot pound-force is the moment about an axis that applies one pound-force at a radius of one foot.

Unit

The value in Système International units is given by multiplying the following exact factors:
This gives the exact conversion factor:
The name "pound-foot", intended to minimize confusion with the foot-pound as a unit of work, was apparently first proposed by British physicist Arthur Mason Worthington.
Despite this, in practice torque units are commonly called the foot-pound or the inch-pound. Practitioners depend on context and the hyphenated abbreviations to know that these refer to neither energy nor moment of mass.
Similarly, an inch-pound is the torque of one pound of force applied to one inch of distance from the pivot, and is equal to. It is commonly used on torque wrenches and torque screwdrivers for setting specific fastener tension. An inch-ounce is a smaller unit, equal to of an inch-pound.