Home Wikituition Browse all terms Categories
Random term
Thermodynamics & Statistical Physics

Most Probable Speed

The particle speed corresponding to the maximum peak of the Maxwell-Boltzmann speed distribution curve.

Governing formula v_mp = √(2 kB T / m) = √(2 R T / M)
SI unit m/s

In depth

Represents the speed possessed by the largest number of particles in a gas. Note $v_{mp} < v_{avg} < v_{rms}$ ($1 : 1.128 : 1.225$).

Examples in the real world

Most probable speed of Nitrogen ($N_2$) molecules in air at 300 K being approximately $422 m/s$.