PHY201

Fundamentals of Thermal Physics

4.00

Undergraduate

1. The Kinetic Theory of Gases Macroscopic and microscopic description of matter, thermodynamic variables of a system, State function, exact and inexact differentials, Basic assumptions of the kinetic theory, Ideal gas approximation, deduction of perfect gas laws, Maxwell’s distribution law, root mean square and most probable speeds. Collision probability, Mean free path from Maxwell’s distribution. Degrees of freedom, equipartition of energy. Nature of intermolecular interaction : isotherms of real gases. van der-Waals equation of state.
2. Transport Phenomena Viscosity, thermal conduction and diffusion in gases. Brownian Motion: Einstein’s theory, Perrin’s work, determination of Avogardo number.
3. Thermodynamics of Photon Gas Spectral emissive and absorptive powers, Kirchoff’s law of blackbody radiation, energy density, radiation pressure. Stefan-Boltzmann law, Planck’s law
4. First Law of Thermodynamics Zeroth law and the concept of temperature. Thermodynamic equilibrium, internal energy, external work, quasistatic process, first law of thermodynamics and applications including magnetic systems, specific heats and their ratio, isothermal and adiabatic changes in perfect and real gases.
5. The Second Law of Thermodynamics and its Statistical Interpretation (a) Second law of thermodynamics: different formulations and their equivalence (b) Entropy: The statistical postulate. (c) Equilibrium of an isolated system: Temperature (d) Illustration: The Schottky defects. (e) Equilibrium of a system in a heat bath: Boltzmann distribution; Kinetic interpretation of the Boltzmann distribution.
6. Thermodynamic Functions Enthalpy, Helmholtz and Gibbs’ free energies; Chemical potential, Maxwell’s relations; thermodynamic equilibrium and free energies.
7. Change of State Equilibrium between phases, triple point, Gibbs’ phase rule and simple applications. First and higher order phase transitions, The phase equilibrium and the ClausiusClapeyron equation,. JouleThomson effect, third law of thermodynamics
8. Applications of Thermodynamics. (a) Heat engines and Refrigerators: Derivation of limits on efficiency from the laws of thermodynamics; Carnot cycle; realistic cycles for internal combustion engines, steam engines, and refrigeration (b) Thermodynamics of rubber bands: Gibbs free energy, Entropy (c). Paramagnetism: A paramagnetic solid in a heat bath. The heat capacity and the entropy. An isolated paramagnetic solid. Negative temperature.