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Electric motor

An electric motor, is a machine which converts electrical energy into mechanical (rotational or kinetic) energy. A basic electric motor is pictured below.
Figure 9.8: Basic electric motor / electric generator
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In the motor a current is passed through a loop which is immersed in a magnetic field. A force exists on the top leg of the loop which pulls the loop out of the paper, while a force on the bottom leg of the loop pushes the loop into the paper. The net effect of these forces is to rotate the loop in the direction indicated.