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A non conducting ring having a charge q ...

A non conducting ring having a charge q uniformly distributed over its circumference is placed ona rough horizontal suface. A vertical time varying magnetic field `B=4t^(2)` is switched on at time t-0. Mass if the ring is m and radius is R. The ring starts rotating after 2seconds. The coefficient of friction between the ring and the table is

A

`(4qmR)/(g)`

B

`(2qmR)/(g)`

C

`(8qR)/(mg)`

D

`(qR)/(2mg)`

Text Solution

Verified by Experts

The correct Answer is:
C
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