Question

A rubber ball is dropped from rest from a height h. The ball bounces off the floor and reaches a height of 2h/3. How can we use the principle of the conservation of mechanical energy to interpret this observation?

a) During the collision with the floor, the floor did not push hard enough on the ball for it to reach its original height.

b) Some of the ball’s potential energy was lost in accelerating it toward the floor.

c) The force of the earth’s gravity on the ball prevented it from returning to its original height.

d) Work was done on the ball by the gravitational force that reduced the ball’s kinetic energy.

e) Work was done on the ball by non-conservative forces that resulted in the ball having less total mechanical energy after the bounce.

Please explain how to figure this out

Answer 1

Option e.

In this case the work is done on the ball by nonconservative forces that resulted in the ball having less total mechanical energy after the bounce.

Step-by-step explanation:

• This is the type of nonelastic collision when a moving ball hits the ground.
• Although the conservation of mechanical energy possessed by the ball which is the sum of P.E and K.E., but kinetic energy is not conserved.
• The non conservative force did the work on the ball that after bouncing lost some of the mechanical energy of that ball.
• The kinetic energy in the beginning is converted in some other energy like friction and air resistance in this case.