Question
Write two differences between electromagnet and permanent magnet.
✓
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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