(C) The activity $A$ of a radioactive sample is defined as the rate of decay,given by $A = |\frac{dN}{dt}| = \lambda N$,where $N$ is the number of rad

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(C) The activity $A$ of a radioactive sample is defined as the rate of decay,given by $A = |\frac{dN}{dt}| = \lambda N$,where $N$ is the number of radioactive nuclei present.The number of moles in the sample is $n = \frac{m}{M}$.The total number of nuclei $N$ is given by $N = n \times N_A = \frac{m}{M} \times N_A$.Substituting this into the activity formula,we get $A = \lambda \times \frac{m}{M} \times N_A = \frac{\lambda m N_A}{M}$.

Class 12 Physics Nuclei Law of Radioactivity by Rutherford and Soddy and Half Life and Mean Life

Medium

$A$ sample of radioactive material has mass $m$,decay constant $\lambda$,and molar mass $M$. If the Avogadro constant is $N_A$,what is the initial activity of the sample?

A
$\lambda m$
B
$\frac{\lambda m}{M}$
C
$\frac{\lambda m N_A}{M}$
D
$m N_A e^{\lambda}$

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Nuclei

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Law of Radioactivity by Rutherford and Soddy and Half Life and Mean Life

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$A$ sample of radioactive material has mass $m$,decay constant $\lambda$,and molar mass $M$. If the Avogadro constant is $N_A$,what is the initial activity of the sample?

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