(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A rock contains three^{207}Pb nuclei for every^{235}U nucleus. Determine the age of the rock assuming all of the^{207}Pb was formed through the decay of uranium. (The half life of^{235}U is 0.71x10^{9}).

2. Relevant equations

N=N_{0}e^{-λt}

3. The attempt at a solution

So the decay constant is ln 2/T_{1/2}=9.76x10^{-10}. So

N_{0}= 1 e^{(9.76x10-10)t}

But the problem is I don't know how to find N_{0}, the remaining nuclei. How could I find it using the information given? They just say there are 3 Pb's for every uranium nucleus... How do we find the amount decayed so we can subtract it from the total to get the remaining N_{0}?

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# Homework Help: Nuclear physics question

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