Heat And Thermodynamics

A cubical box of side \(2 \mathrm{~m}\) contains helium gas. It was observed that in a time of 1 second, an atom travelling with the root-mean-square speed parallel to one of the edges of the cube, made 250 hits with one of the walls, without any collision with other atoms. The average kinetic energy of the helium gas is Take \(R=\frac{25}{3} \mathrm{~J} / \mathrm{mol}-\mathrm{K}\) and \(\mathrm{kB}=1.38 \times 10^{-23} \mathrm{JK}{ }^{-1}\)