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प्रश्न
State any two advantages of electromagnets over permanent magnets.
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उत्तर
Following are the advantages of electromagnet over permanent magnets.
1) An electromagnet can produce a strong magnetic field
2) The strength of the magnetic field of an electromagnet can be easily changed by changing the current in its solenoid.
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संबंधित प्रश्न
Write two characteristics of a material used for making permanent magnets ?
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Which of the following is most suitable for the core of an electromagnet?
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