General Comments: The animation is apparently simulating ideal hard sphere collisions, a situation that the non-virtual demonstration approximates quite well. The physics appears to be accurate for the ideal case that is being simulated.
It is very easy to use. This is a nifty, simple animation that might well be extremely useful for an on-line illustration or could be usefully incorporated into a tutorial or homework assignment regarding collisions, giving students direct access to the demonstration.
The reviewers do not see a clear use in and of itself for this animation in an instructional setting that isn?t better served by the actual demonstration. Perhaps it could be used in a large lecture hall where it would be difficult for students in the back rows to see the standard demonstration device or as an online reminder of the demo done in class. As a lecture-demo, it would be preferable to use some sort of video camera set-up to enable the viewing of the real-world device.