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 : (1) development of air current when the plate is placed. (2) induction of electrical charge on the plate (3) shielding of magnetic lines of force as aluminium is a paramagnetic material. (4) electromagnetic induction in the aluminium plate giving rise to electromagnetic damping?
ritesh kashyap
12 Years agoGrade 11
1 Answer
Saurabh Koranglekar
6 Years ago
Dear student
The oscillating coil produces a time-varying magnetic field. It causes eddy current in the aluminum plate which causes anti-torque on the coil, due to which it stops. Thus, electromagnetic induction in the aluminum plate giving rise to electromagnetic damping.
Regards
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