Energy

Energy is the ability to do work or produce change. There is only one kind of energy, but it may exist in many forms including potential, kinetic, electrical, strain, chemical, internal, and heat. No matter in what form the energy exists, energy is a product of the force on a body and the distance over which the energy is exerted. [E=Fxd] Work is a form of energy.

Any system or machine gives back exactly the same amount of energy put into it. Some energy may be used for work, while other energy may be wasted as heat or stored as potential energy.

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