Which of the following is an example of potential rather than kinetic energy?

A. The muscle contractions of a person moving grass

B. Water rushing over Niagra falls

C. Light flashes emitted by a firefly

D. A molecule of glucose

E. The flight of an insect foraging for food

D. A molecule of glucose

Explanation:

Potential energy is defined as the energy that is stored, or conserved, in an object or substance. The act of contracting muscles, emitting light flashes, flying or water moving are all dissipating energy and, thus, do not represent an example of kinetic energy. On the other hand, a molecule of glucose stores energy and therefore is an example of potential energy.