Electromotive force

Electrical action produced by a non-electrical source

In electromagnetism and electronics, electromotive force (emf, or EMF) or electromotance, denoted E {\displaystyle {\mathcal {E}}} , is an energy transfer to an electric circuit per unit of electric charge, measured in volts. Devices called electrical transducers provide an emf by converting other forms of energy into electrical energy. Other types of electrical equipment also produce an emf, such as batteries, which convert chemical energy, and generators, which convert mechanical energy.

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