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