100 Matter and Energy Energy is usually defined as the capacity to do work, where work means the moving of matter against a force. Anything which has the capacity to push matter from one place to another has energy. Energy can either be kinetic or potential .
Kinetic energy is that energy intrinsic in an object which has motion.
Potential energy, on the other hand, is energy intrinsic in an object not because of its motion but because of its position with respect to other objects. In any system, the total energy present is distributed partly as kinetic energy and partly as potential energy. Familiar forms of both kinetic and potential are heat, light, sound, electric, and chemical energy. These may transform one into another, and it is usually these transformations which are observed. The explosions and fireballs that accompany certain chemical reactions represent transformations in which part of the chemical energy is converted into other forms of energy, such as heat, light, and sound.