Question
A small, conducting circular loop is placed inside a long solenoid carrying a current. The plane of the loop contains the axis of the solenoid. If the current in the solenoid is varied, the current induced in the loop is:
  1. Clockwise.
  2. Anticlockwise.
  3. Zero.
  4. Clockwise or anticlockwise depending on whether the resistance in increased or decreased.

Answer

  1. Zero.

Explanation:

The angle between magnetic field and area vector is 90°, so the flux associated with coil is zero. Although magnetic field is changing but flux is remaining constant equal to zero, so emf induced and hence current in the loop is equal to zero.

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