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Question
The diagram shows a coil wound around a U shape soft iron bar AB.
1) What is the polarity induced at the ends A and B when the switch is pressed?
2) Suggest one way to strengthen the magnetic field in the electromagnet
3) What will be the polarities at A & B if the direction of current is reversed in the circuit?
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Solution
1) A - South, B - North
2) Increasing the number of turns of coils, increasing current.
3) A-North, B - South
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