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Question
Describe briefly three main useful application of eddy currents ?
Solution
Application of Eddy currents:
(i) Induction furnace: When a piece of metal, which is to be converted into an alloy, is wound by the circular conducting coil, a high frequency alternating current is passed through the coil which in turns changes the magnetic flux associated with the metal. This produces strong eddy currents that generate a large amount of heat in the metal block and melts it easily.
(ii) Electric brakes: Electromagnets are placed in the trains just above the rails. Whenever these electromagnets are activated, eddy currents are produced in such a way that they oppose the motion and stop the train.
(iii) Induction motor: A rotating magnetic field produces strong eddy currents in the rotor of the motor, which starts rotating in the direction of the field.
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