Thermodynamics - Introduction
                              Thermo :heat
  Kinetic Theory of           dynamics : motion
  Gases
  Thermodynamics      Thermodynamics is the study of motion of heat.
  State Variables             Most thermodynamical variables depends on the temperature
  Zeroth law of
  thermodynamics              of the system.
                              Although it is dynamics - one interesting aspect - Time however
                              does not enter in most of the thermodynamic equations. Did
                              you notice that Temperature did not enter in most of the
                              equations in Mechanics, and will notice that it does not enter
                              Quantum Mechanics and Electrodynamics equations !!
                              Thermodynamics describes average properties (that generally
                              does not depend on details of position/velocity) of macroscopic
                              (matter that contains atoms or molecules) matter in equilibrium.
                              Such as Volume, Pressure, Temperature (called as
                              thermodynamic coordinates or variables or parameters).
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               Thermodynamics - Introduction Contd ..
 Kinetic Theory of   A state of macroscopic matter where average properties does
 Gases               not change with time - Equilibrium State (usually no external
 Thermodynamics
 State Variables     driving force exists).
 Zeroth law of       In thermodynamics, the average macroscopic properties of the
 thermodynamics
                     system are not independent of each other. Measure a subset of
                     properties and then calculate the remaining using
                     thermodynamic relations.
                     You will see that the laws (4 in number) of thermodynamics are
                     general.Theydescribeanysysteminequilibrium-awide
                     variety of physical and chemical systems.
                     Thermodynamics was formulated in 18th and 19th Century -
                     before we knew in detail the structure of matter. Hence it works
                     even if matter constituents are not fully known.
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              Albert Einstein and Thermodynamics
 Kinetic Theory of
 Gases
 Thermodynamics
 State Variables
 Zeroth law of
 thermodynamics
               Thermodynamics is the only physical theory of universal content
               which, within the framework of applicability of its basic concepts, I
               am convinced will never be overthrown.
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                     Planck, Black Body Radiation and Thermodynamics
                                                            Ihadnoalternativebuttotackletheproblemagain
                                                            ...   from the side of thermodynamics. In fact, my
  Kinetic Theory of
  Gases                                                     previous studies of the Second Law of Thermody-
  Thermodynamics                                            namics came to stand me in good stead now, for at
  State Variables                                           the very outset I hit upon the idea of correlating not
  Zeroth law of                                             the temperature of the oscillator but its entropy with
  thermodynamics                                            the energy... While a host of outstanding physicists
                                                            worked on the problem of the spectral energy dis-
                                                            tribution both from the experimental and theoretical
                                                            aspect, every one of them directed his e↵orts solely
                                                            towards exhibiting the dependence of the intensity of
                                                            radiation on the temperature. On the other hand, I
                                                            suspected that the fundamental connection lies in the
                                                            dependence of entropy with the energy ... Nobody
                                                            paid any attention to the method which I adopted
                                                            and I could work out by calculations completely at
                                                            my leisure, with absolute thoroughness, without fear
                                                            of interference or competition.
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