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Question
How does an electromagnet differ forma permanent magnet?
Solution
| Electromagnet | Permanent magnet | ||
| 1. | It is a temporary magnet. |
1.
|
As the name suggests, it is a permanent magnet. |
| 2. | It can produce very strong magnetic force. | 2. | It produces a comparatively weak magnetic field. |
| 3. | Its polarity can be changed by changing the direction of current in the coil. | 3. | Its polarity is fixed and cannot be changed. |
| 4. | Its strength can be changed by changing the number of turns or by changing the current. | 4. | Its strength cannot be changed. |
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