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Magnetism And Matter — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsMagnetism And Matter1 Mark
MCQ
A thin diamagnetic rod is placed vertically between the poles of an electromagnet. When the current in the electromagnet is switched on, then the diamagnetic rod is pushed up, out of the horizontal magnetic field. Hence, the rod gains gravitational potential energy. The work required to do this comes from:
  • A
    The current source.
  • B
    The magnetic field.
  • C
    The induced electric field due to the changing magnetic field.
  • D
    The lattice structure of the material of the rod.
✓

Answer

  1. The current source.

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