posted by Anonymous .
A 1000 kg sports car accelerates from 0 to 30 m/s in 10 s. What is the average power of the engine?
Power is work done per unit time.
Average power is increase in work/energy divided by the duration for the increase.
initial kinetic energy, Ei = 0
final kinetic energy, Ef
= (1/2)1000 30² kg-m²-s-2
duration, t = 10 s
= 45,000 W (or joules-s-1