Quote:
Originally Posted by Letum
I believe that for a fixed density, terminal velocity rises exponentially so
large rocks are going to vaporise you.
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Whoa, wait a second..... that doesn't sound right somehow...at least not in this case.
How large does a rock have to be for its exponential rise in terminal velocity to really make a difference? Aren't most meteorites travelling at thousands of kilometers per hour relative to the Earth anyways? Aren't the ones that actually hit the ground necessarily large or dense because they are the only ones that can survive the heat when they enter the atmosphere? Are you talking about terminal velocity or acceleration due to gravity?
I'm finding this kind of difficult to phrase, but I guess my question is; "What kind of mass would a rock have to have for gravity to be a significant factor in its acceleration towards the surface? Wouldn't its velocity relative to the earth be the more important factor? And if so, couldn't even a small metorite (even if it began as a large one, vaporise you since force is a function of mass x velocity squared?"
I think I'm probably misunderstanding you but I'd be grateful for a little clarification.
Thanks
