Question

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. developement of air current when the plate is placed
• B. induction of electrical charge on the plate
• C. shielding of magnetic lines of force as aluminium is a paramagnetic material
• D. Electromagnetic induction in the aluminium plate giving rise to electromagnetic damping

Answer 1

Answer: (D)

Electromagnetic induction in the aluminium plate giving rise to electromagnetic damping

Answer 2

$\vec{B}$ Electomagnetic damping