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Anyway what I am trying to figure out is something I have been thinking about for many years. The dinosaurs didn’t die from a big explosion or anything just that the earths gravity increased and made them less competitive to smaller creatures. I have heard bone mass decreases for astronauts so I am think it must increase if gravity increased. Also I am not looking for a number but an understanding of what a creature would weigh with the increase of matter that has been hitting the earth over time. The 37,000# number is what I found on the internet as a theory to what is being added to the earth ever year so over 60 million years there must by an increaseHope someone can help

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closed as too localized by David Z Feb 20 '13 at 2:37

This question is unlikely to help any future visitors; it is only relevant to a small geographic area, a specific moment in time, or an extraordinarily narrow situation that is not generally applicable to the worldwide audience of the internet. For help making this question more broadly applicable, visit the help center.If this question can be reworded to fit the rules in the help center, please edit the question.

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Hi user21164, and welcome to Physics Stack Exchange! This is a site for conceptual questions about physics, not for homework help or for people to do calculations for you. If you can edit your question to ask about the specific physics concept that is giving you trouble, I'll be happy to reopen it. See our FAQ and homework policy for more information. –  David Z Feb 20 '13 at 2:41
    
You need the average mass of a piece of "space junk," a number I don't know off hand and don't feel like looking up (your source for that figure should have it, probably?). Once that is known the problem is trivial. –  Michael Brown Feb 20 '13 at 2:43
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Not sure how I am to ask a question here. This is not homework I am over 50. I think I need a Layman to scientist translator ;-) –  Chuck Kay Feb 20 '13 at 3:06
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Thank You Michael, I will keep checking back –  Chuck Kay Feb 20 '13 at 3:33
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The mass of meteorites and dust hitting the Earth is about 5e7kg/year, so since the Earth's creation 4.5Gyears ago it has accumulated about 2e17kg. The mass of the Earth is about 6e24kg, so it has increased in mass by about 0.000003% since it's creation. I think we can safely assume this is not the reason for the dinosaurs dying out :-) –  John Rennie Feb 20 '13 at 8:49

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