Motion heat conversion

Thermal Properties. Before considering conventional thermal properties such as conductivity it is appropriate to consi r briefly the effect of temperature on the mechanical properties of plastics. It was stated earlier that the properties of plastics are markedly temperature dependent. This is as a result of their molecular structure. Consider first an amorphous plastic in which the molecular chains have a random configuration. Inside the material, even though it is not possible to view them, we loiow that the molecules are in a state of continual motion. As the material is heated up the molecules receive more energy and there is an increase in their relative movement. This makes the material more flexible. Conversely if the material is cooled down then molecular mobility decreases and the material becomes stiffer. 

A fuel cell is equivalent to a generator it converts a fuel s chemical energy directly into electricity. The main difference between these energy conversion devices is that the fuel cell acccomplishes this directly, "without the two additional intermediate steps, heat release and mechanical motion. 

Energy The capacity for doing work as measured by the capability of doing work (potential energy) or the conversion of this capability to motion (kinetic energy). Most of the world s convertible energy comes from fossil fuels that are burned to produce heat that is then used as a transfer medium to mechanical or other means in order to accomplish tasks. 

Although the term heat energy is commonly encountered in casual conversation, strictly speaking there is no such entity. The term is commonly used in place of the more precise term energy of thermal motion, where thermal motion is random molecular motion, as in the motion of molecules in a gas. Nor is heat stored Only energy is stored, and heat is one of the modes by which it may be increased or extracted, see also Chemistry and Energy Energy Explosions Temperature Thermochemistry Thermodynamics. 

---