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A thin non conducting disc of radius R i...

A thin non conducting disc of radius `R` is rotating clockwise (see figure) with an angular velocity `omega` about its central axis which is perpendicular to its plane Both its surfaces carry+ve charges of unifrom surface density Half the disc is in a region of a unifrom unidirectional magnetic field `B` parallel to the plane of the disc as shown Then
.

A

A

B

B

C

C

D

D

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The correct Answer is:
A
A thin alminium disc spinning freely is brouth to rest because of eddy currents induced in the disc.
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PRADEEP-ELECTROMAGNETIC INDUCTION & ALTERNATING CURRENT-Exercise
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