A 0145kg baseball rebounds off of a wall The rebound speed i

A 0.145-kg baseball rebounds off of a wall. The rebound speed is one-third of the original speed. By what percent does the kinetic energy of the baseball change in the collision with the wall? Where does the energy go?

Solution

Percantage change in Kinetic energy is given

% change in KE =KE_new-KE_old/KE_old = (1/2)mV_new² -(1/2)mV²/(1/2)mV_new²

Given V_new=V/3

% change in KE =[(V/3)²-V²]/V² =-0.8888 or -88.88 %