Joshua hooks a rubber band between his thumb and forefinger. He moves his fingers apart, stretching the rubber band. With a quic
k, sudden motion, he bends his thumb forward so that the rubber band slips off. What happens next? A. The chemical potential energy stored in Joshua's body changes to elastic potential energy in the rubber band.
B. The elastic potential energy stored in the rubber band changes to heat energy.
C. The chemical potential energy stored in Joshua's body changes to kinetic energy.
D. The elastic potential energy stored in the stretched rubber band changes to kinetic energy.
Answer: D. The elastic potential energy stored in the stretched rubber band changes to kinetic energy.
Explanation: According to the law of conservation of energy, energy can neither be created nor be destroyed. It can only be transformed from one form to another.
Elastic potential energy is the energy stored as a result of applying a force to deform an elastic object. The energy is stored until the force is removed. When the force is removed, the object gets back to its original shape.
Kinetic energy is the energy possessed by a body by virtue of its motion.
Different substances have different molecular masses. Thus, equal masses have different numbers of atoms, molecules, or moles. On the other hand, equal numbers of moles of different substances have different masses.
