Use the Initialize simulation function to start the simulation. The simulation will begin with the particle and gas atoms being equal in size and having the mass of hydrogen (which has a relative mass of 1). The particle will scatter off the gas atoms present and change its kinetic energy with each collision. When the gas particles begin to heat up you can reset them to their original velocities using the Reset velocities function.

Changing the particle mass will introduce a new particle with 5 eV of energy into the gas. This will eventually heat the gas requiring you to reset velocities. The gas can be set to a mass of 1 (Use Hydrogen) or a mass of 40 (Use Argon)

Using Mass 0.001 is the equivalent of Positronium. By choosing this mass you can see that such a small particle takes a very long time to impart its own energy to the surrounding particles. While this simulation is clearly a long ways away from accounting for true quantal nature of the particles involved, it is useful for building your intuition for the processes occurring in the gas.

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