A mechanic pushes a 2000 kg car from rest to a speed of v, doing 4750J of work in the process. During this time, the car moves 27.0 m. Neglecting friction between car and road, find each of the following. a) What is the speed v? b) What is the horizontal force exerted on the car? A mechanic pushes a 2000 kg car from rest to a speed of v, doing 4750J of work in the process. During this time, the car moves 27.0 m. Neglecting friction between car and road, find each of the following. a) What is the speed v? b) What is the horizontal force exerted on the car?
Explanation / Answer
Mass of the car is m = 2000 kg Workdone W = 4750 J distance travelled is d = 27.0m a ) speed of the car is 1/2 m v^2 = F * d 1/2 * 2000 kg * v^2 = 2000kg * 9.8 m/s^2 * 27.0 m v = 11.5 m/s b ) Horizontal force exerted on the car is W = F * d 4750 J = F * 27.0m F = 4750 J / 27.0 m = 175.9 N