MCQ
The material suitable for making electromagnets should have:
- AHigh retentivity and high coercivity.
- BLow retentivity and low coercivity.
- CHigh retentivity and low coercivity.
- DLow retentivity and high coercivity.
✓
Answer
- High retentivity and low coercivity.
Explanation:
An electromagnet is necessary for the material that even if the current is turned off, the material losses its magnetic field. So, it should be made from such a material that its retentivity is very high. And there must be enough coercion force for the material which can restore its pre-magnetization state. For that its coercivity should be as minimum as possible.
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