The <Van der Waals equation> replaces the freely available volume by $V-Nb$ to represent short-range repulsion and <excluded volume>. The attractive mean field reduces the <pressure> by $aN^2/V^2$: particles near the boundary are pulled back into the gas, lowering their <momentum> transfer to the walls. Both are effective corrections, rather than an exact microscopic interaction law.

Solution

Past exam of the physics course of the year 4 of the natural sciences course of the University of Cambridge / 2016 / Paper 1 / Section B / B2 / a / Solution

 Solution (source code)