A 1500-kg car accelerates from rest to 25 m/s in 7.0 s. what is the average power delivered by the engine? (1 hp = 746 w)

The solution for this is:

Work done = force * distance = m*a*d and power = energy/time

The vo=0 and vf = 25 m/s and t=7 sec. This gives ...

3.6 m/s^2 as acceleration and d=87.5 meters and thus F=ma = 5400 N.

Energy = 5400*87.5 = 4.7E5 Joules (2 sig. figs) and Power = 67,500 Watts or 90 HP (2 sig. figs again).