Infinite Rocks Collide: Is the Impact Elastic?

AI Thread Summary
The discussion revolves around the theoretical collision between an infinitely large rock moving slowly and an infinitely small rock moving at an extremely high speed. It highlights that elastic collisions are nearly impossible in practical scenarios, with molecular interactions being the closest example. The conversation emphasizes that using terms like "infinitely fast" is not scientifically acceptable, suggesting instead to use relative terms like "really fast." Participants compare the scenario to a bullet hitting a mountain, noting that while a bullet at high speeds would have a significant impact, even lower speeds would still yield noticeable effects. Overall, the discussion critiques the feasibility of the proposed collision scenario while exploring the implications of mass and velocity in collisions.
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If an infinitely large rock is traveling infinitesimally slow along a straight line and an infinitesimally small rock is traveling infinitely fast towards the infinitely large rock along the same axis, is the collision elastic?
 
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In practice elastic collisions are almost impossible. As far as I know only molecules in the kinetic theory are treated with elastic collisions.

And terms as "infinitely fast" for matter is not acceptable.
If you change your words to 'really big', 'really small', 'really slow', and 'really fast', I would say the small rock would just shatter and pulverize.
 
The problem you're setting is just like shooting a bullet in a mountain. What do you think would happen?
 
Dr Lots-o'watts said:
The problem you're setting is just like shooting a bullet in a mountain. What do you think would happen?

I think that is why he is specifying the high/low mass and high/low velocity. According to e=mc2 a bullet would have no effect on a mountain. But a bullet traveling at .9999c would have a very noticeable effect on a mountain.

EDIT: Not that a bullet wouldn't have still a very noticeable effect on a mountain at speeds of lower than .9999c.
 

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