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A horizontal telephone wire 10^(3) m lon...

A horizontal telephone wire `10^(3)` m long is lying along east west in earth's magnetic field. It falls freely to the ground from a height of 10m. The emf induced in the wire when the wire strikes emf induced in the wire when the wire strikes the ground will be `(B_(H)=0.32xx10^(-4)T,g=9.8m//s^(2))`

A

0.248 V

B

0.448 V

C

0.348 V

D

0.684 V

Text Solution

Verified by Experts

The correct Answer is:
B
`e=B_(H)lv=B_(H)lsqrt(2gh)`
`=0.32xx10^(3)sqrt(2xx9.8xx10)`
`=0.248V`
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