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Electric generator

The basic electric generator uses a set-up similar to the electric motor of Fig. 9.8, but in this case one does not send a current through the wire loop, but instead rotates it in the magnetic field. This rotation comes from the action of falling water (in a hydroelectric plant) or steam (in a coal or nuclear power plant) hitting turbine blades, causing them to turn. A changing magnetic field subsequently is established through the plane of the wire loops, which causes a current to be generated. In this way mechanical or rotational energy is converted to electrical energy. It turns out that as the loop rotates through one complete revolution the direction of the current reverses, which is an AC current.