Explained: What is Equipartition of Energy in Physics?

BY Team Aakash Byju's

When we consider a gas molecule inside a container, we know particles are in motion.

The pressure inside a pressure cooker increases under the application of heat. So how does this happen?

When we heat a container, the pressure on the particles increases, and the particles move with more speed.

If the energy is not equally distributed among the particles, pressure exerted by each particle would be different.

Energy distribution purely depends on the degree of freedom. The degree of freedom is the number of directions in which an independent motion can be seen.

The Law of Equipartition of Energy helps us understand the distribution of energy given to increase the pressure on the particles.

Law of Equipartition of Energy tells us that the total energy applied will be distributed equally among the degrees of freedom for any dynamic system in thermal equilibrium.

Since all properties of gas molecules depend on energy, this law is also known as the ‘Law of Statistical Mechanics’.

The kinetic energy of a gas atom is expressed as : For each molecule with a degree of freedom 3, kinetic energy upon a gas molecule = (3/2) KT

So, E = (3/2) KT holds good for all monatomic gases,  E = (5/2) KT holds good for diatomic molecules as the degree of freedom is 5.

For triatomic gases, the deg of freedom is 7.