A foot-pound (ft·lb or ft·lbf) is a unit used in the Imperial system to measure torque or energy (work). It is commonly used in the automotive industry to measure engine torque, but it can also be used as a unit of energy or work.

Foot-Pound as Torque:

Torque is the ability of a force to rotate an object, and its formula is as follows:
τ=r×Fτ=r×F

Where:

    ττ represents torque.
    rr represents the distance from the pivot point at which the force is applied, i.e., the lever arm.
    FF represents the applied force.

In this case, if a force (pound-force) is applied along a lever arm (feet), the torque is measured in foot-pounds.

Foot-Pound as Energy:

The foot-pound unit is also used to measure energy or work, where 1 foot-pound represents the amount of work or energy done when 1 pound of force is applied over a distance of 1 foot.

Conversion:

To convert between foot-pounds and Newton-metres, you can use the following formula:
1 ft\cdotplb≈1.35582 Nm1ft\cdotplb≈1.35582Nm

So, if a torque value is 1 foot-pound, it is equivalent to approximately 1.35582 Newton-metres.