MCQ
How will the force between the two poles change if the two poles are connected by an iron rod keeping the distance between two magnetic poles constant ?
- AIncreases.
- BDecreases.
- CRemains same.
- DNone of these.
✓
Answer
- Increases.
Explanation:
An iron rod placed between the poles of a magnet provides a better path than air for the magnetic flux. The flux density in iron is greater than it is in air; therefore, iron is said to have a high permeability. Hence the force between the poles increases. Also the Iron rod gets magnetised with north pole at the end in contact with south pole and south pole at the end in contact with the north pole of the bar magnet.
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