Maxwell-Boltzmann Velocity Distribution Function

What
This function describes the fraction of particles having a given range of speeds. The number of gas particles per unit volume having speeds between v and v + dv is given by

$$n_{v}\textrm{d}v = n(\frac {m}{2\pi kT})^{3/2} e^{-mv^2/2kT}4\pi v^2 \textrm{d}v$$