Friday, November 21, 2014

Introduction to Statistical Mechanics | Ehsan Physics Center

In Mechanics, we study about motion and force.
Statistics Means Counting , we take chances in it.

There are three systems according to inter molecular forces:
1) Gasses System
2) Liquid System
3) Solid System
Pressure of Gas represent whole gasses system. General Results depend upon the individual units. Individual Units are knows as Microscopic Properties. The Bulk Property depends upon the individual property. Here, pressure of gass is microscopic property.
Velocity, momentum, force are called microscopic properties.
Pressure, volume, energy, and mass of gass (N) are called macroscopic properties.

Macroscopic property is whole of system, but microscopic property is too small according to whole system. According to microscopic property study of macro property is called Statistical Mechanics. After all results we take average because we cannot measure exact value. If particle belongs to different environment then statistical mechanics will also be different. The Particles that have half spin motion they have different statistical mechanics rules and the particles that have integral multiple spin the will have different statistical rules.

There are three types of statistical mechanics
1) Maxwell, Boltzmann (Classical Statistical Mechanics)
It is about the atoms and molecules.
2) Fermic - Dirac (Quantum Statistical Mechanics)
It is about the electrons (half or integral)
3) Bose - Einstein (Quantum Statistical Mechanics)
It is about inside the atoms, light emission, and phonons.

For General Knowledge:
Motion of phonons is always integral multiple and motion of proton and neutron is always half spin.