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The Physics of Colliding Balls

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Re: The Physics of Colliding Balls

#21
post #12

For an interesting exploration of how even the simple physics of two blocks hitting one another can lead to surprising conclusions, I'd highly recommend this 3Blue1Brown video called "Why do colliding blocks compute pi?": https://www.youtube.com/watch?v=jsYwFizhncE

>> Why do colliding blocks compute pi? A lot of times with math I don't think the word "why" should be used. Those blocks computing pi was a good example where they "proved that they compute pi", but not really why . What is the real distinction I'm trying to make here and how to explain it?

There is no “why”, there just “is”.

Re: The Physics of Colliding Balls

#22

Earlier quoted context omitted.

Actually, I believe that it can be elastic, if the friction is so great that the surfaces do not slip the entire time they are in contact.

til how rubber bouncy balls work

Yes. They can bounce back and forth due to the spin reversing. I believe each time they make contact with the floor, high friction causes of spent to stop, while they undergo a rotational deformation, which then reverses direction.
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