SCOPE AND IMPORTANCE OF THERMODYNAMICS

Thermodynamics is a sub-area of physics, of chemistry, and of most engineering disciplines. Unlike mechanics, in which only work and mechanical energy are defined, thermodynamics deals with all forms of energy and energy transfer, including thermal energy and heat. Therefore, thermodynamics is a continuation of mechanics. Together, mechanics and thermodynamics provide a much more comprehensive, detailed, and quantitative description of our physical world, and of actual physical and chemical processes.

The two major “laws,” or “hypotheses,” or “postulates,” of mechanics (see Chapter 2) and six new principles of thermodynamics, which are covered in detail in this book (see Section 1.7.1), provide highly important predictions as to what processes are physically possible, or feasible, and what processes are not possible. Consequently, these eight principles act as the “constitution” of the physical, chemical, biological, and engineering sciences. This “constitution” has many secondary consequences, or implications, that are important in all these areas, and are discussed in various books on thermodynamics, physical chemistry, materials science, and related areas. Therefore, technical professionals should learn and understand at least the key principles and ideas of thermodynamics.

Thermodynamics is important in everyday life. The general public should be informed about what processes are possible in energy production and use, materials production and use, food production and use, and waste generation and treatment. The availability of energy sources, especially renewable and sustainable energy, is essential for the quality of life of all human beings. Biological and physiological processes should also follow the thermodynamic principles. Thus, medical professionals, business people, attorneys, and other non-technical people should have some appreciation of what processes make physical and thermodynamic sense, so that they can make informed decisions.