A train of mass 100 tons `(1` tons `=1000kg)` runs on a meter gauge track ( distance between the two rails is `1m)`. The coefficient of friction between the rails and the train is `0045`. The train is powered by an electric engine of `90%` efficiency. The train is moving with uniform speed of `72 kmph` at its highest speed limilt . Horizontal and vertical component of earth's magnetic field and `B_(H)=10^(-5)T` and `B_(V)=2xx10^(-5)T`. Assume the body of the train and rails to be perfectly conducting.
The electrical power consumed by the trains is

Options

A. `1.11MW`
B. `1MW`
C. `0.50 MW`
D. `0.90 MW`

Answer

B

Explanation

`(B)` Power `=(mu mg .v)/("fractional efficiency ")`
`=(0.45xx10^(2)xx10^(3)xx10xx20)/(0.9)=10^(6)` watt