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Question
The following figure shows a coil wound around a soft iron bar XY.
- State the polarity at the ends X and Y as the switch is pressed.
- Suggest one way of increasing the strength of electromagnet so formed.
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Solution
- The polarity at X is north and at Y is south.
- By increasing the number of turns of winding in the solenoid, the strength of the electromagnet can be increased.
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