Question

A truck of mass 500 kg travelling at 40 m/s is brought to rest by applying the brakes. The truck comes to rest after travelling 20 m, after applying the brakes. What is the kinetic energy of the truck?

Answer 1

Kinetic Energy at first= 1/2mv^2 = 1/2*500*1600 = 400000J
KE after stopping = 0 (velocity is 0)