Conservative force—a force with the property that the work done in moving a particle between two points is independent of the path it takes.

A conservative force is a force with the property that the work done in moving a particle between two points is independent of the path taken.

Equivalently, if a particle travels in a closed-loop, the net work is done (the sum of the force acting along the path multiplied by the distance travelled) by a conservative force is zero.

A conservative force is dependent only on the position of the object. If a force is conservative, it is possible to assign a numerical value for the potential at any point.

When an object moves from one location to another, the force changes the potential energy of the object by an amount that does not depend on the path taken.

Gravity and spring forces are examples of conservative forces.

If a force is not conservative, then defining a scalar potential is not possible, because taking different paths would lead to conflicting potential differences between the start and endpoints.

Non-conservative forces transfer energy from the object in motion (just like conservative force). Still, they do not transfer this energy back to the potential energy of the system to regain it during reverse motion.

Instead, they transfer the energy from the system in an energy form, which cannot be used by force to transfer it back to the object in motion. Friction is one such non-conservative force.