A ball hits the floor and rebounds after an inelastic collision. In this case

Options

A. the momentum of the ball just after the collision is the same as that just before the collision
B. the mechanical energy of the ball remains the same in the collision
C. the total momentum of the ball and the earth is conserved
D. the total energy of the ball and the earth is conserved.

Answer

C, D

Explanation

(c,d): (a) It is incorrect because the momentum of the ball changes in magnitude as well as direction. (b) It is incorrect because during collision some mechanical energy is converted into heat and sound energy. (c) is correct. (d) is correct.