When you add energy to matter, the particles move faster and the matter heats up.
Explanation:
The atoms and molecules that make up matter are never completely immobile. Even if you are looking at a relatively static, still material. On the contrary, these particles are always animated by a motion whose amplitude depends on the physical state of matter.
This motion is a form of kinetic energy called thermal energy. The greater the agitation of particles in a body, the greater the thermal energy of that body.
