A car mass 1500kg is traveling at 20 ms^-1 (72 km h^-1)?

Question

what is the kinetic energy of the car?

brakes are applied to stop the car.if the braking force is 750 N ?(equal to half the weight of the car)'what is the braking distance?

15 hours ago - 3 days left to answer.

Answer 1

Kinetic energy

= (1/2)mv^2

= (1/2) * (1500) * (72000/3600)^2

= 3 x 10^5 J.

Work done = loss of K.E.

=> 750 * d = 3 x 10^5

=> d = (3 x 10^5) / 750

= 400 m.