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Topic: Nuclear decay  (Read 2853 times)

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Offline hvard78

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Nuclear decay
« on: May 03, 2011, 04:51:33 PM »
If you have a 1000g sample of U-238, how much will be left after 2,500,000,000 years?


Do I do like 2.5 billion/2, then do 2^x=that number, then divide 1000 by x?
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Offline SirRoderick

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Re: Nuclear decay
« Reply #1 on: May 03, 2011, 04:54:31 PM »
What is the half-life of U-238 and what does that figure mean?
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Offline hvard78

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Re: Nuclear decay
« Reply #2 on: May 03, 2011, 04:59:18 PM »
I just searched it up. It has a half life of 4.468 billion years
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Offline hvard78

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Re: Nuclear decay
« Reply #3 on: May 03, 2011, 05:02:15 PM »
WAITT
is it 555.6 g?
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Offline SirRoderick

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Re: Nuclear decay
« Reply #4 on: May 03, 2011, 05:04:55 PM »
Well then, keeping that in mind.
N(t) = N0* e^{-lambda*t}

How could you use this formula, which should be familiar I think?

EDIT
Hang on I'll check

EDIT 2
I'm getting 675g on a rough pass. (didn't really pay attention to roundings and significant numbers)
« Last Edit: May 03, 2011, 05:22:47 PM by SirRoderick »
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