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प्रश्न
Point out three differences between an electromagnet and a bar (or permanent) magnet.
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उत्तर
| Electromagnet | Bar Magnet |
| 1. An electromagnet exhibits a much stronger magnetic field. | A bar magnet is not able to exhibit a strong magnetic field. |
| 2. Its polarity can be reversed by reversing the direction of current flowing in the turns of the coil (or solenoid). | Its polarity is fixed. |
| 3. It is a temporary magnet, it behaves as a magnet only when the current flows through the solenoid. | It is a permanent magnet and cannot be readily demagnetized. |
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