i have been given an equation of,(adsbygoogle = window.adsbygoogle || []).push({});

delta(N) = N(t).delta(t)/T

where N(t) is the number of atoms left at time t, and T is the half life. Using a constant time and variable half lifes i have to come up with a formula to calculate the remaining atoms left over.

the formula i was able to obtain from my working is

delta(N) = N0/e^(t.sq) / 2T

i am not sure if this equation is write and also my problem is that i have no idea of how i obtained this formula from the original one.

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# Radioactivity of an unknown isotope

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