MCQ
Permanent magnets should have:
- AHigh retentivity and low coercivity.
- BLow retentivity and high coercivity.
- CHigh retentivity and high coercivity.
- DLow retentivity and low coercivity.
✓
Answer
- High retentivity and high coercivity.
Explanation:
Permanent magnets should have high retentivity so that a strong magnetic field persists on removal of magnetic field.
Permanent magnets should have high coercivity so that external magnetic field in opposite direction cannot easily demagnetize the magnet.
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