MCQ
The material suitable for making electromagnets should have:
- AHigh retentivity and high coercivity.
- BLow retentivity and low coercivity.
- ✓High retentivity and low coercivity.
- DLow retentivity and high coercivity.
✓
Answer
Correct option: C.
High retentivity and low coercivity.
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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