The pressure of an ideal gas is written as Here E refers to

1. Molecules of ideal gas have negligible interaction between them. This means that force acting due to each other while they are in motion is almost zero.


2. In such cases where force acting on particle is zero, particle moves in uniform motion and in straight line according to newton’s first law of motion.


3. So, in kinetic theory of ideal gas, molecules of gas are moving in straight line. Hence, they will only have translational kinetic energy.

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