Conservative force

Conservative forces are those that possess certain properties:

1. The work it does on a particle is independent of it's trajectory.

2. The work done on a particle that moves along a closed trajectory (where the initial and final positions are the same, or d_{i = df}) = 0) is zero.

When the only forces present in a system are conservative, mechanical energy is be conserved.

Examples of Conservative Forces:

Gravitational Force.

Force performed by a spring.