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A metallic ring of radius a and resistan...

A metallic ring of radius a and resistance R is held fixed with its axis along a spatially uniform magnetic field whose magnitude is `B_(0)` sin `(omega t)`. Neglect gravity. Then,

A

The current in the ring oscillates with a frequency of `2omega`

B

The joule heating loss in the ring is proportional to `a^(2)`

C

The force per unit length on the ring will be proportional to `B_(0)^(2)`

D

The net force on the ring is non-zero

Text Solution

Verified by Experts

The correct Answer is:
C
`(dF)/(dL)=B/R((dB.A)/dt)`
Where `B=B_(0)sinomegat`.
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