Why root mean square Velocity is taken while calculating pressure exerted by gas on walls of container?
One of the quantities fundamental to the calculation of pressure is the energy of the gas, which in the case of an ideal gas is the sum of the kinetic energies of the molecules = no. of molecules * average KE / molecule. Since KE is proportional to the square of the velocity, when all the molecules have equal mass the average KE can be calculated using RMS velocity. That is why you see that in the calculations.
