Find the power of an engine which can draw a train of `400` metric ton up the inclined plane of `1` in `98` at the rate `10 ms^(-1)`. The resistance due to friction acting on the train is `10 N` per ton.

Explanation

Given `sin theta = 1/98, m = 400 xx 10^(3) kg `
frictional force ` f = 10 xx 400 = 4000 N`
velocity `v = 10 ms^(-1)`
`therefore "Power" P = (mg sin theta + f ) v`
`therefore P = [( 400 xx 10^(3) xx 9.8 xx 1/98) + 4000] xx 10`
`= 440000 W = 440 KW`