Thermal energy is the sum of sensible heat and latent heat.

Definitions

System of N particles

According to the equipartition theorem, it is possible to define thermal energy. In a system of N molecules, each with f degrees of freedom, and if there are no other (non-quadratic) temperature-dependent forms of energy, then the total thermal energy of the system is:¹

To note, U_thermal is almost never the total energy of a system; for instance, there can be static energy that doesn't change with temperature, such as bond energy or rest energy (E=mc²).

Other definitions

Thermal Energy comes from the movement of atoms and molecules in matter.

Thermal energy per particle is also called the average translational kinetic energy possessed by free particles given by equipartition of energy.²

Thermal energy is the difference between the internal energy of an object and the amount that it would have at absolute zero.^{citation needed} It includes the quantity of kinetic energy due to the motion of the internal particles of an object, and is increased by heating and reduced by cooling.

In a monatomic ideal gas, the thermal energy is exactly given by the kinetic energy of the constituent particles.^{citation needed}

See also

References

1. ^ Schroeder, Daniel, R. (2000). Thermal Physics, New York: Addison Wesley Longman. ISBN 0201380277. 
2. ^ Thermal energy – Hyperphysics