# Work

Therefore, the overall work exerted on a body is equal to the variation of its kinetic energy. In the presence, however, of a conservative force field, that is in the absence of dissipative effects, the work done is equal to the variation of potential energy between the ends of the path. The work done by a force is zero if the displacement is zero or if it has no components along the direction of the displacement. The work $$W$$ done by a constant force of magnitude $$F$$ on a point that moves a displacement $$s$$ in a straight line in the direction of the force is the product:
$W=F\cdot s$