We already know about two types of energy: potential energy and kinetic energy.  There are many more types of energy: chemical, nuclear, electric.... However, the two which we have talked about are part of everyday phenomena.  Historically they are the ones which have been used since antiquity.

We are going to study a situation where objects only possess two types of energy: free fall.

LEARN:

The sum of the kinetic and potential energy of an object is called Mechanical Energy.