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Question
A bar magnet is moved in the direction indicated by the arrow between two coils PQ and CD. Predict the directions of induced current in each coil.
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Solution
According to Lenz’s law the polarity of the induced emf is such that it opposes the change in magnetic flux responsible for its production.
Since North Pole of bar magnet is receding away from the coil so the right end of the coil will develop South Pole i.e. induced current as seen from the left end will be anticlockwise.
Again, since South Pole is pushing towards the second coil so the left end of the coil will develop South Pole in order to repel it and decrease the flux i.e. induced current as seen from the left end will be clockwise.
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