Relation Between Work, Force and Displacement

Work is measured as the product of force and the displacement in the direction of the force.

Work = force × displacement in the direction of the force.

If force and displacement are in the same direction, you can easily find work done by finding their product. But if force and displacement are in different directions the work done is obtained by finding the product of force and the projection of displacement in the direction of the force.

Example: A person carrying a heavy load on his head and moving on a level road does no work against gravity, because, there is no component of displacement in the direction of force of gravity.

The SI Unit of work is newton-metre (Nm) or joule (J). 1 J work is done when a body moves through a distance of 1 m under a force of 1 N, in the direction of force.