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Assertion:A disc-shaped mahnet is leviat...

Assertion:A disc-shaped mahnet is leviated above a superconductiong material that has been cooled by liquid nitrogen.
Reason:Superconductors repal a magnet.

A

If both assertion and reason are true and reason is the correct explanation of assertion.

B

If both assertion and reason are truw but reason is not correct explanation of assertion

C

If assertion is true but reason is false

D

If both assertion and reason are false.

Text Solution

Verified by Experts

The correct Answer is:
A
Since superconductors exist only below a certain critical temprature and above that temprature they behave like normal materials.When magnet is placed above superconductor and cooled using liquid nitrogen.The induced magnetic field inside the superconductor is exactly equal and opposite in direction to the applied magnetic field,so that they cancel within the super conductor.These poles wil repel each other and the force of repulsion is enough to float the magnet.
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