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प्रश्न
The following diagram shows a spiral coil wound on a hollow carboard tube AB. A magnetic compass is placed close to it. Current is switched on by closing the key.
- What will be the polarity at the ends A and B?
- How will the compass needle be affected? Give reason.
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उत्तर
- A - North pole, B - South pole.
- The north end of the compass is repelled and moves away because a north pole is generated at end A, where current flows anticlockwise and enters the negative pole of the battery.
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