Kinetic Theory and Thermal Energy

Kinetic Theory of Matter: All matter is composed of tiny particles (atoms and molecules) that

are always in motion.Temperature: A measure of the average translational kinetic energy per particle in a substance.

Higher kinetic energy means higher temperature. Temperature has no upper limit but a definite lower

limit: Absolute Zero ($0\text{ K}$ or $-273.15^\circ\text{C}$), where all translational kinetic energy has

been removed.Thermal Energy: The total energy (kinetic and potential) of the submicroscopic

particles in a substance. A large pot of lukewarm water has more thermal energy than a small cup of boiling water.Heat:

The flow of thermal energy due to a temperature difference, moving from a substance of higher temperature

to a substance of lower temperature. It is energy in transit, measured in Joules