Maxwell–Boltzmann distribution

Summary

The Maxwell–Boltzmann distribution is the distribution of molecular velocities in a dilute gas in thermal equilibrium. Each velocity component, measured relative to the bulk velocity, is normally distributed with variance $kT/m$, where $T$ is the temperature and $m$ the molecular mass. It is the equilibrium of the Boltzmann equation, the state in which collisions no longer change the distribution. Maxwell found it in 1860, and Boltzmann later derived it from his kinetic equation. See the definition.