This is a simple model created with EJS.
The mass for two particles are the same initially.
Use mouse to drag the slider to change the velocity for one of the particle.
You will find the velocity exchanged when collision occurred.
Then, drag the slider to modify the mass for the particles, the situation getting complicated.
However, the momentum is always conserved.

VIEW or DOWNLOAD ejs xml source
    Available translation (locale: translators) click link to toggle view of translation done by that user
  1. English(en):rk123
then click to translate strings for selected locale.

Press the Alt key and the left mouse button to drag the applet off the browser and onto the desktop.