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Magnetism And Matter — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsMagnetism And Matter1 Mark
MCQ
The material suitable for making electromagnets should have:
  • A
    High retentivity and high coercivity.
  • B
    Low retentivity and low coercivity.
  • C
    High retentivity and low coercivity.
  • D
    Low retentivity and high coercivity.
✓

Answer

  1. 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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