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Reading skimming
A very useful strategy is reading a text quickly to get a general
idea of the kind of information it contains. You can then decide
which parts of the text are worth reading in more detail later,
depending on your reading purpose. This strategy is called
skimming.

Step 2

Skim this text and identify the paragraphs, which contain informa-
tion on each of these topics. The first one has been done for you.

a) What electric motors are used for ( paragraph 1) ?
b) Why the armature turns?
c) The commutator
d) Electromagnets
e) Effect of putting magnets together.
f)The armature paragraph
In an electric motor an electric current and magnetic field produce
a turning movement. This can drive all sorts of machines from
wrist - watches to trains. The motor that is used for example for a
washing machine. It is a universal motor that can run on direct
current or alternating current.

An electric current, running through a wire produces a
magnetic field around the wire. If an electric current flows around
a loop of wire with a bar of iron through it, the iron becomes
magnetized. It is called electromagnets: one end becomes a North
Pole and the other a South Pole, depending on which way the
current is flowing around the loop.
If you put two magnets close together, like poles-torn
example, two north poles - repel each other, and unlike poles
attract each other. In a simple electric motor, a piece of iron with
loops of wire round it, called an armature, is placed between the
north and south poles of a stationary magnet known as the field
magnet. When electricity flows around the armature wire, the iron
becomes an electromagnet.

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