What are eddy currents ? Mention two applications of eddy currents.

Explanation

The circulating currents set up in bulk pieces of metal through a magnetic field are called eddy currents.
Practical applications of eddy currents :
(i) Magnetic brakes work on the principle of eddy currents. When a magnetic field is applied
on the rotating drum, eddy currents are induced in the drum. The eddy currents decreases steadily in magnitude as the train slows down. Thus the braking effect is quite smooth.
(ii) Energy meters are instruments used to measure the electrical energy consumed by the electrical appliances. A metal disc in the energy meter rotates due to eddy currents. Other applications.
(iii) Induction (ac) motor (rotor) is a low resistance coil placed in a rotating magnetic field. Eddy currents in a rotor, rotates it in a direction of the magnetic field.
(iv) Eddy currents of high frequencies are used in the induction furnace which is used to prepare alloys by melting the constituent metals.