THE ELECTRIC MOTOR

​The Electric Motor

• armature

• permanent stationary magnet

• commutator

• drive shaft

• coil of wire

• battery

• pulley

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​A simple electric motor consists of a cylindrical armature, with a coil wound around it, which is positioned between the north and the south poles of a permanent magnet.

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​A battery feeds current into the coil.

This produces a magnetic field around the coil transforming the magnet into an electromagnet.​

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​The magnetic field interacts with the magnetized armature forcing it to rotate, as the north pole of the permanent magnet attracts the south pole of the armature.

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​The current is reversed every half-turn by the commutator.

This has the effect of reversing the north and the south poles of the armature thus keeping it in a state of rotation.​

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​The continuous turning motion of the armature drives the motor.

​Many varieties of electric motor have been developed based on the same basic principle:

t​hey use the force of magnetism to transform electrical energy into mechanical energy.

​The motor has two essential parts:

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1. the rotor > which moves

2. the stator > which is stationary

​Usually the rotor revolves inside the stator and turns an axle attached to it. The axle carries the mechanical energy to do the work of the motor.

​The main division in electric motors is between:

• those which operate on direct current (DC), for example from a battery;

• those which run on alternating current (AC) from the mains.​