Physics · Electromagnetic induction: Faraday's law, induced emf and current, Lenz's law, eddy currents, self and mutual inductance

Assertion An emf is induced in a long solenoid by a bar magnet that moves while

Assertion An emf is induced in a long solenoid by a bar magnet that moves while totally inside the solenoid along the axis of the solenoid. Reason As the magnet moves inside the solenoid the flux through individual turns of the solenoid changes.

  • A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
  • B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
  • C. Assertion is correct but Reason is incorrect
  • D. Assertion is incorrect but Reason is correct

Step-by-step solution

As the bar magnet moves inside the solenoid, the magnetic flux through each turn changes with time due to the changing position of the magnet relative to the turn. According to Faraday's law of induction, a changing flux induces an emf in each turn, resulting in a net emf in the solenoid. Thus the reason correctly explains the assertion.
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