A superconducting ring of radius 'a' and inductance L is located in a uniform magnetic field of induction B. The plane of ring is parallelto B and the current in the ring is zero. Then the ring is turned through 90^(@) so that plane is perpendicular to the field. What is the work done in turning the ring?

A superconducting ring of radius 'a' and inductance L is located in a

1.	A superconducting ring of radius 'a' and inductance L is located in a uniform magnetic field of induction B. The plane of ring is parallelto B and the current in the ring is zero. Then the ring is turned through 90^(@) so that plane is perpendicular to the field. What is the work done in turning the ring?
Answer» `(PI^(2)a^(4)B^(2))/(2L)` `(pi^(2)a^(2)B^(2))/(2L)` `(pi a^(2)B^(2))/(2L)` `(pi^(2)a^(4)B^(2))/(4L)`. Answer :A

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