A `500-kg` car, moving with a velocity of `36kmh^-1` on a straight road unidirectionally, doubles its velocity in `1min`. The average power delivered by the engine for doubling the velocity is

Options

A. (a) `750W`
B. (b) `1050W`
C. (c) `1150W`
D. (d) `1250W`

Answer

D

Explanation

`u=10ms^-1`, `v=20ms^-1`
Work done=Increase in kinetic energy
`=1/2xx500[20^2-10^2]=(500xx30xx10)/(2)`
`Power=(500xx30xx10)/(2xx60)=1250W`