Physics
The diagram in figure shows a small magnet placed near a solenoid AB with it's north pole N near the end A. Current is switched on in the solenoid by pressing the key K.
(a) State the polarity at the ends A and B.
(b) Will the magnet be attracted or repelled? Give a reason for your answer.
Answer
(a) The direction of current in the solenoid at the face A is anticlockwise, so it will have the North polarity and the face B of solenoid at which the current is clockwise will have the South polarity.
(b) The magnet will be repelled because the end A of the solenoid becomes North pole as current at this face is anticlockwise and it repels the north pole of the magnet.
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