Aball falling through the air has
(a) both kinetic energy because it still has a distance to move before it hits the ground and potential energy because it is moving
(b) only kinetic energy
(c) only potential energy
(d) both potential energy because it still has a distance to move before it hits the ground and kinetic energy because it is moving.

when a car stops, the brakes heat up because of friction. what is this an example of?
(a) energy being destroyed
(b) one form of energy being converted to another
(c)periodic motion
(d) elastic motion