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

Options

A. clockwise
B. anticlockwise
C. dependent on whether current in solenoid is decreased or increased
D. zero

Answer

D

Explanation

Magnetic field due to solenoid is along the axis of solenoid. Plane of the loop is parallel to the axis and hence angle between magnetic field and area vector becomes `90^(@)`. For any magnitude of current flowing in solenoid, magnetic flux linked with the coil remains zero. Hence no emf will be induced in the loop even if current flowing through the solenoid is changed.