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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.
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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संबंधित प्रश्न
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- Give one use of the device mentioned in part (b).
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The diagram below shows an insulated copper wire wound around a hollow cardboard cylindrical tube. Answer the questions that follow:
- What are the magnetic poles at A and B when the key K is closed?
- State two ways to increase the strength of the magnetic field in this coil without changing the coil.
- If we place a soft iron bar at the centre of the hollow cardboard and replace the DC source with an AC source then will it attract small iron pins toward itself when the current is flowing through the coil?
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Differentiate between a circular coil and a solenoid.
