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Magnetism And Matter — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsMagnetism And Matter1 Mark
MCQ
Permanent magnets should have:
  • A
    High retentivity and low coercivity.
  • B
    Low retentivity and high coercivity.
  • ✓
    High retentivity and high coercivity.
  • D
    Low retentivity and low coercivity.
✓

Answer

Correct option: C.
High retentivity and high coercivity.

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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