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

The two rails of a railway track, insulataed 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 separted by 1m.

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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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HC VERMA-ELECTROMAGNETIC INDUCTION-EXERCISE
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  2. A 10 m wide spaceraft moves through the interstellar space at a speed ...

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  4. A right angled triangle abc, made from a metallic wire, moves at a uni...

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  5. A copper wire bent in the shape of a semicircle of radius r translates...

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  6. A wire of length 10cm translates in a direction making an angle of 60^...

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  7. A circular copper ring of radius r translates in its plane with a cons...

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  8. Shows a wire sliding on two parallel, conducting rails placed at a se...

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  9. Shows a wire of length l which can slide on a U- shaped rail of neglig...

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  10. Consider the situation of the previous problem. (a) Calculate the forc...

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  11. Consider the situation shown in . The wire PQ has mass m, resistance r...

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  12. A rectanguar frame of wire abcd has dimensions 32cm X 8.0 cm and a tot...

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  13. Shows a metallic wire of resistance 0.20 Omega sliding on a horizontal...

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  14. A wire ab of length l, mass m and resistance R slides on a smooth, thi...

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  15. Consider the situation shown in figure. The wires P1Q1 and P2Q2 are ma...

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  16. Suppose the 19 Omega resistor of the previous problem is disconnected....

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  17. Consider the situation shown in . The wire PQ has a negligible resist...

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  18. The current generator I g, shown in . Sends a constant current I throu...

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  19. The current generator ig, shown in , sends a constant current I throu...

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  20. The system containing the rails and the wire of the previous problem i...

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