College Physics with MasteringPhysics 7th Edition by Jerry Wilson,Anthony Buffa,Bo Lou

Exercise 53

A 0.20-kg object with a horizontal speed of 10 m/s hits a wall and bounces directly back with only half the original speed. (a) What percentage of the object's initial kinetic energy is lost: (1) 25%, (2) 50%, or (3) 75% (b) How much kinetic energy is lost in the ball's collision with the wall