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The two rails of a railway track, insul...

The two rails of a railway track, insulated form each other and from the ground, are connected to a millivoltmeter. What will be the reading of the millivoltmeter when a train travels on the track at a speed of `180km h^(-1)`? The vertical component of earth's magnetic field is `0.2 X 10^(-4)` and the rails are seprated by 1m.

Text Solution

Verified by Experts

Here`v=180km//h=50m//s,`
`B=0.2xx10^(-4)T,L=1m.`
`E=B theta l=0.2xx10^(-4)xx50`
`=10^(-3)V.`
So, the voltmeter will record 1 mV.
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