The disintegration rate of a certain radioactive sample at any instant is 4250 disintegrations per minute. 10 minutes later, the rate becomes 2250 disintegrations per minute. The approximate decay constant is :
$\left(\right.$Take $\left.\log _{10} 1.88=0.274\right)$
Solution
<p>${A_0} = 4250$</p>
<p>$A = 2250 = {A_0}{e^{ - \lambda t}}$</p>
<p>$\Rightarrow {{2250} \over {4250}} = {e^{ - \lambda t}}$</p>
<p>$\Rightarrow \lambda (10) = \ln \left( {{{4250} \over {2250}}} \right)$</p>
<p>$\lambda (10) = 0.636$</p>
<p>$\lambda = 0.063$</p>
About this question
Subject: Physics · Chapter: Atoms and Nuclei · Topic: Radioactivity
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