Engine Engine An engine or motor is a machine designed to convert one form of energy into mechanical energy. Heat engines burn a fuel to create heat which is then used to do work. Internal combustion engines are heat engines that burn fuel in a combustion chamber to extract work from the pressure of expanding gases. Electric motors convert electrical energy into mechanical motion; pneumatic motors use compressed air; and clockwork motors in wind-up toys use elastic energy. In biological systems, molecular motors, like myosins in muscles, use chemical energy to create forces and eventually motion. The word "engine" derives from
Potential energy to the gravitational potential energy, thus The more formal definition is that potential energy is the energy difference between the energy of an object in a given position and its energy at a reference position. Potential energy is closely linked with forces. If the work done by a force on a body that moves from "A" to "B" does not depend on the path between these points (if the work is done by a conservative force), then the work of this force measured from "A" assigns a scalar value to every other point in space and defines a scalar potential