Write two differences between electromagnet and permanent magnet. - Vidyadip

Question

Write two differences between electromagnet and permanent magnet.

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Answer

Electro Magnet	Permanent Magnet
1. These can be magne-tised and demagnetised again and again.	1. These can not be magnetised and demagnetised again and again.
2. These are made of substances having high magnetic suspectibility and low retentivity e.g. Iron.	2. These are made up of sub-stances having high coercitivity and retentivity, e.g. steel or alloys.

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