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.

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

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

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

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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.

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

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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.

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

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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

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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.

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For triatomic gases, the deg of freedom is 7.

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