Question

A car of mass 1510 kg traveling at 22 m/s is at the foot of a hill that rises 115 m in 2.2 km. At the top of the hill, the speed of the car is 12 m/s. Find the average power delivered by the car's engine, neglecting any frictional losses. (In watts)

Answer 1

Answer 2

$deacceleration , a =\frac{u^2-v^2}{2s} =\frac{22^2-12^2}{2*2.2*1000}=0.0773m/s^2$

$sin(\theta)= 115/2200=0.0522$

$mgsin(\theta)-F = ma$

$F =mgsin(\theta)- ma=656.52 N$

$average\: \: power =\frac{work\: done\: by\: force }{time} =(F*s)/t=11164.78W$