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A conducting disc of radius R is placed ...

A conducting disc of radius `R` is placed in a uniform and constant magnetic field `B` parallel to the axis of the disc.With what angular speed should the disc be rotated about its axis such that no electric field develops in the disc (the electric charge and mass are `e` and `m`)

A

`(eB)/(2m)`

B

`(eB)/(m)`

C

`(2pim)/(eB)`

D

`(pim)/(eB)`

Text Solution

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The correct Answer is:
B
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