Making MagnetsMaking Magnets

Chapter 22

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A magnetic object can be made into a magnet by:

• The Stroking Method

• The Electrical Method

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The Stroking Method

• Also known as the Touch Method.

• A magnetic object is stroked many times in the same direction with a magnet.

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The Stroking Method

You will need:

a magnet

a magnetic object

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Try picking up iron filings with a magnetic object,

for example, an iron nail. 1

The iron filings do not cling to

the nail.

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Now, stroke the iron nail about 20 times with one pole of a bar magnet.

Stroke with the same pole and always in the same direction!

2

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Try picking up iron filings with the iron nail again.

The iron filings cling to the nail! The iron nail

has become a magnet. It has been

magnetised!

3

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The Electrical Method

• Magnets are made using electricity.

• Magnets made by this method are called electromagnets.

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An electromagnet is made by coiling an electrical wire round a magnetic object, e.g. an iron nail many times. The ends of the wire are connected to a battery.

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Danger!

Never use electricity from the mains to make an electromagnet!

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At a glance…

A magnetic object can be made into a magnet by:

The Stroking Method

The Electrical Method

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At a glance…

The Stroking Method

A magnetic object is stroked many times in the same direction with a magnet.

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At a glance…

The Electrical Method

An electromagnet is made by coiling an electrical wire round a magnetic object many times. The ends of the wire are connected to a battery.