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The attraction and repulsion between the poles of this
armature magnet and the poles of the field magnet make the
armature turn. As a result, its north pole is close to the south pole
of the field magnet. Then the current is reversed so the north pole
of the armature magnet becomes the south pole. Once again, the
attraction and repulsion between it and the field magnet make it
turn. The armature continues turning as long as the direction of the
current, and therefore its magnetic poles, keeps being reversed.
To reverse the direction of the current, the ends of the
armature wire are connected to different halves of a split ring
called a commutator.
Current flows to and from the commutator through small
carbon blokes called brushes. As the armature turns, first one half
of the commutator comes into contact with the brush delivering the
current and then the other, so the direction of the current keeps
being reversed.

Source: Adapted from “I snide out: Electric Motor”, Education
Guardian.

Language study. Describing function.

Try to answer this question:

1. What does an electric motor do?
2. When we answer a question like this, we describe the
function of something, we can describe the function of an
electric motor in this way:
3. An electric motor converts electrical energy to mechanical
energy.
4. We can emphasize the function like this:
5. The function of an electric motor is to convert electrical
energy.

Step 3

Match each of these motor components to its function, and then

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