For the Maxwell-Boltzmann speed distribution, the ratio of the root-mean-square speed (vrms) and the most probable speed (vmax) is Given : Maxwell-Boltzmann speed distribution function for a collection of particles of mass m is \(f(v)=(\frac{m}{2\pi k_BT})^{3/2}4\pi v^2\text{exp}(-\frac{mv^2}{2k_BT})\) where, v is the speed and kBT is the thermal energy.