Thermodynamics

Thermodynamics is the field of science that studies the conversion of energy in the form of heat to other forms, mechanical in particular. There are many processes that convert energy from one form to another. For example burning wood converts chemical energy in the wood to heat and if that heat is used to produce steam to perform work then the heat has been converted to mechaniical work which can be used to power a machine, produce electricity or many other jobs. In this instance the chemical energy was converted to heat then the heat was converted to mechanical work.

A thermosiphon would be another example of thermodynamics where heat is used to move a liquid or gas from a lower level to a higher point. This happens because a hot gas or liquid is lighter than a cool gas or liquid. Thermosiphon is often used in passive solar systems to move the heated air or water without an outside energy source being used to pump the air or liquid.