School of Physics Lecture Demonstration Manual

He-7 Maxwell Boltzmann distribution

Published: Monday 13 March 2006 - Updated: Monday 28 March 2011


To demonstrate the distribution of velocities in a gas via a mechanical analogue.


Kinetic theory apparatus


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Maxwell Boltzmann


The Kinetic theory apparatus consists of a chamber containing hundreds of small ball bearings representing the atoms in a gas. The lower portion of the chamber is connected to a mechanical vibrator which imparts a continuous motion to the "atoms" An exit hole at the side of the apparatus leads to a segmented plastic container. The atoms exiting the chamber with different velocities are captured by this container. Those atoms with greater velocity reach a different channel in the histogramming bin. A few minutes of operation allows the velocity distribution of the particles to be built up.

Safety notes

Electrical Safety 


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