The Mom: Potential energy is stored energy based on its position, like water at the top of Niagara Falls that is waiting to spill over the top. For example, a rock on the ground is a rock, but a rock being held by a boy at the top of a 10-story building has potential energy. The potential energy in the rock at the top of the building becomes kinetic energy once the rock hits the ground. You could say that the potential energy in the rock at the top of the building is equal to the kinetic energy of the rock once it has hit the ground. So what do you think kinetic energy means?
The 8 y.o.: That the boy is Canadian?