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A cylindrical bar magnet is rotated abou...

A cylindrical bar magnet is rotated about its axis (Fig EP 6.3). A wire is connected from the axis and is made to touch the cylindrcial surface through a contact. Then

A

a direct current flows through the ammeter A.

B

no current flows through the ammeter A.

C

an alternating inusodial current flows through the ammeter A with a time period `T = (2pi)/(omega)`

D

a time varying non-sinusoidal current flows through the ammeter A.

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