Possible to get breaking speeds by manipulating momentum of balls.

[KatieWoe]

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OS
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Problem Description
Found by a user and reported to @amanda-phet:

Someone told me about a Collision Lab bug! They broke the sim with some extreme things. I didn't quite follow but took a video of him explaining it. He said the students got it going 145k the speed of light and the sim broke.

I was able to reproduce this using a simpler method.

1. Go to the second screen
2. You only need two balls. Set one at max mass and one at min mass
3. Set both at top speed.
4. Pause the sim
5. Step forward until collision makes small ball faster
6. Make small ball big and big ball small
7. Repeat 5 and 6 until you get ridiculous speeds

Note that the sim breaks well before a crash happens. The balls will step forward once and then stop moving, whether you press step forward or press play. They will un stop for another step forward when you change the masses. This still requires rather absurd speeds, though I didn't notice exactly when it happened.

Discussion from Slack:

I think this is using knowledge of momentum, and is just fun "let's try to break this" behavior. So I don't think we should spend time on any "fix" for this.

Marking as won't fix, but leaving open since there is the extra element.

Visuals:

PXL_20240926_215419502.TS.mp4

[kathy-phet]

@arouinfar - I think even with this additional info Katie shared, we should still not fix. It feels pretty odd to pause and change things in this very manipulated way. What do you think?