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A wire of length 2.5 km and resistance 3...

A wire of length 2.5 km and resistance `35 Omega` has fallen from a height of 10m in earth's horizontal field of `2 xx 10^(-5) T`. The current through the wire is

A

0.02 A

B

0.002 A

C

0.2 A

D

2A

Text Solution

Verified by Experts

The correct Answer is:
A
`I=(e)/(R)=(Blv)/(R)=(Blsqrt(2gh))/(R)`
`I=(2xx10^(-5)xx2.5xx10^(3)xxsqrt(2xx10xx10))/(35)`
`I=0.02A`
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