Thermodynamics

Thermodynamics is the study of heat and its transformation into mechanical energy. The word stems from Greek words meaning "movement of heat."

The science of thermodynamics was developed by Benjamin Thompson (1753-1814), an American-born British scientist. Thermodynamics focuses on how heat moves and is converted to and from other forms of energy. Thompson was the first to discover that heat flows from hot to cold, not the other way around, by drilling a hole in a metal ball and observing how the ball's heat was transferred to water.

When the law of conservation of energy is applied to the study of heat and its transformation into kinetic energy, it becomes the first law of thermodynamics: all the energy transferred between a system and its surroundings must be accounted for as heat and work.

If we add heat to a system, it can increase the internal energy of the system, if it remains in the system, or do external work, if it leaves the system.