A car of mass `500kg` moving with a speed `36kmh` in a straight road unidirectionally doubles its speed in `1min`. Find the power delivered by the engine.

Explanation

Its initial speed `v_1=(36000)/(3600)=10ms^-1`
If the car doublese its speed, finally its speed becomes `v_2=20ms^-1`.
Change in KE of the car `=DeltaKE=(1//2)mv_2^2-(1//2)mv_1^2`
During `Deltat=1min=60s`
the power delivered by the engine,
P=Work done/Time Taken=`(|DeltaKE|)/(Deltat)`
`=(1/2xxm[v_2^2-v_1^2])/(Deltat)`
`=(1//2xx500[20^2-10^2])/(60)=1250W`