Laws Of Thermodynamics

Laws of thermodynamics refers to heat and work transport in thermodynamic reactions. The thermodynamic laws are basics of physics and other related science. In ancient days Aristotle defined undetermined entity of thermodynamic process. Historical experiments were accepted after the investigation report of Second law of thermodynamics by Sadi Carnot in 1824. First principle of thermodynamics was given by Rudolf Clausius and second principle of thermodynamics was given by William Thomson in 1860. As years rolled on principles became laws. Josiah Willard Gibbs defined absolute laws of thermodynamics as first law of thermodynamics and second law of thermodynamics in his Graphical methods of thermodynamic fluids. Later second and third laws are coupled together as second law of thermodynamic.

Principles of thermodynamic

• Zeroth law of thermodynamics: Defines temperature
• First law of thermodynamics: Defines conservation of energy
• Second law of thermodynamics: Defines entropy and its macroscopic behavior
• Third law of thermodynamics: Defines entropy at absolute zero temperature

Zeroth law of thermodynamics

Each system has its own thermodynamic equilibrium. System exchanges its heat and there exists thermal equilibrium. By this there exists equal temperature throughout the system. It is basic fundamental law of thermodynamics. It refers to transitive relation of thermal equilibrium system. Thermal equilibrium is expressed in terms of equivalence motion.

First law of thermodynamics

First law of thermodynamics delineates the nature of energy. It defines conservation of energy as energy can never be created or destroyed. Energy can only transform its state. In case of isolated system or closed system energy remains the same forever. In open system there is flow of energy. First law of thermodynamics is statistical expression express energy as state of function.

Second law of thermodynamics

Spontaneous thermodynamic process will increase the entropy in general is second law of thermodynamics.  Heat can be transferred from higher level to lower level and not vice versa. For instance heat transfer from refrigerator is possible only to even colder region where fridge is warm by compression. The heat flow from hot fridge to surroundings results in cooling of refrigerator by expansion and cycle gets repeated.

Third law of thermodynamics

Entropy of each system reaches constant minimum at absolute zero temperature. This shows that entropy is dependent on temperature.

Questions:

• What are key concepts of understanding law of thermodynamics?
• Define kinetic energy and law of thermodynamics.
• What are consequences of thermodynamic laws?