A coil is suspended in a uniform magnetic field, with the plane of the coil parallel to the magnetic lines of force. When a current is passed through the coil it starts oscillating, It is very difficult to stop. But if an aluminium plate is placed near to the coil, it stops. This is due to :A. induction of electrical charge on the plateB. shielding of magnetic lines of force as aluminium is a paramagnetic materialC. electromagnetic induction in the aluminium plate giving rise to electromagnetic dampingD. development of air current when the plate is placed

A coil is suspended in a uniform magnetic field, with the plane of the

1.	A coil is suspended in a uniform magnetic field, with the plane of the coil parallel to the magnetic lines of force. When a current is passed through the coil it starts oscillating, It is very difficult to stop. But if an aluminium plate is placed near to the coil, it stops. This is due to :A. induction of electrical charge on the plateB. shielding of magnetic lines of force as aluminium is a paramagnetic materialC. electromagnetic induction in the aluminium plate giving rise to electromagnetic dampingD. development of air current when the plate is placed
Answer» Correct Answer - C Electromagnetic induction in the aluminium plate gives rise to electromagnetic damping and hance the coil stops oscillating.

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