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For a coil of unit area, induction B is ...

For a coil of unit area, induction B is doubled in `0.2s`. Then, the induced e.m.f. is

A

5B

B

10B

C

8 B

D

4B

Text Solution

Verified by Experts

The correct Answer is:
A
`e=(dphi)/(dt)`
`e=(AB_(2)-AB_(1))/(dt)=(2AB_(1)-AB_(1))/(dt)`
`e=(AB_(1))/(dt)=(AB_(1))/(0.2)=(1xxB)/(0.2)=5B`
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