The work done by a force `vecF` during a displacement `vecr` is given by `vecF.vecr`. Suppose a force of 12 N acts on a particle in vertically upward directionand the particle is displaced through 2.0 m in vertically downward direction. Find the work done by the force during this displacement.

Explanation

The angle between the force `vecF` and the displacement `vecr is 180^0`. Thus, the work done is
`W=vecF.vecr`
`=Frcostheta`
`=(12 N)(2.0m)(cos150^0`
=-24N-m=-24J`.