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A uniform but time-varying magnetic fiel...

A uniform but time-varying magnetic field B(t) exists in a circular region of radius a and is directed into the plane of the paper, as shown. The magnitude of the induced electric field at point P at a distance r from the centre of the circular region

A

is zero

B

decreases as` 1/r`

C

increases as r

D

decreases as `1/r^(2)`

Text Solution

Verified by Experts

The correct Answer is:
2
Magnitude of induced electric field (r>a)
`E=(a^(2) dB)/(2pidt)`Thus, the magnitude of the electric field increases linearly from zero at the center of electric field to` (a/2) (dB/dt)` at the edge of circular region of radius a, and then decreases inversely with distance.
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