Statistical Physics: Macrostates and Microstates

Consider some (4, say) distinguishable particles. If we wish to distribute them into two exactly similar compartments in an open box, then the priori probability for a particle of going into any one of the compartments will exactly 1/2 as both compartments are identical. If the four particles are named as a , b, c and d and the compartments as compartment 1 and compartment (2), then following table can be made listing all the possible arrangements. $ Compartment (1)…

Ensemble 1

Statistical Physics: Ensembles

Ensembles: As a system is defined by the collection of a large number of particles, so the "ensembles" can be defined as collection of a number macroscopically identical but essentially independent systems. Here the term macroscopically independent means, as, each of the system constituting an ensemble satisfies the same macroscopic conditions, like Volume, Energy, Pressure, Temperature and Total number of particles etc. Here again, the term essentially independent means the system (in the ensemble) being mutually non-interacting to others, i.e.,…

Rayleigh- Jean’s Law

Lord Rayleigh on classical limes made an attempt to explain the energy distribution in black body radiation, which was completed by Jeans in 1900. The result obtained by then is known as Rayleigh - Jean's Law. Black body emits radiation of continuously variable wavelength right from zero to infinity. This radiation can be imagined as broken up into monochromatic waves. These monochromatic waves originate as a result of a different modes of vibration of the medium, which at that time…