making of magnet
TRANSCRIPT
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
My Pals are Here! Science 3B © 2004 Marshall Cavendish International (Singapore) Private LimitedMy Pals are Here! Science 3B © 2004 Marshall Cavendish International (Singapore) Private LimitedYou are reminded that under the Copyright Act, it is an offence to reproduce or copy any part of this presentation without permission fromYou are reminded that under the Copyright Act, it is an offence to reproduce or copy any part of this presentation without permission from
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At a glance…
The Stroking Method
A magnetic object is stroked many times in the same direction with a magnet.
My Pals are Here! Science 3B © 2004 Marshall Cavendish International (Singapore) Private LimitedMy Pals are Here! Science 3B © 2004 Marshall Cavendish International (Singapore) Private LimitedYou are reminded that under the Copyright Act, it is an offence to reproduce or copy any part of this presentation without permission fromYou are reminded that under the Copyright Act, it is an offence to reproduce or copy any part of this presentation without permission from
Marshall Cavendish International (Singapore) Private Limited.Marshall Cavendish International (Singapore) Private Limited.
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.