Question 9: A man drops a cup from a certain height which breaks into pieces. What energy changes are involved? ANSWER When the cup is in the hands of the man at a certain height, it possesses potential energy depending upon its weight and its height from the ground. When the man drops it, the potential energy is converted to kinetic energy; again dependent on its mass and velocity. When the cup hits the ground and breaks into pieces, the kinetic energy is converted into sound, heat and breaking the cup into pieces.