Sources of electrical energy

This article provides information on the following six methods of producing electric power.Friction: Energy produced by rubbing two material together. Heat: Energy produced by heating the junction where two unlike metals are joined. Light: Energy produced by light being absorbed by photoelectric cells, or solar power. Chemical: Energy produced by chemical reaction in a voltaic cell, such as an electric battery. Pressure: Energy produced by compressing or decompressing specific crystals. Magnetism: Energy produced in a conductor that cuts or is cut by magnetic lines of force.

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