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Nuclei — Physics STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 SciencePhysicsNuclei3 Marks
Question
Consider a radioactive nucleus $A$ which decays to a stable nucleus $C$ through the following sequence$: A \rightarrow B \rightarrow C$
Here $B$ is an intermediate nuclei which is also radioactive. Considering that there are $N_0$ atoms of $A$ initially, plot the graph showing the variation of number of atoms of $A$ and $B$ versus time.
✓

Answer

Consider the situation shown in the graph.
At $t = 0, NA = NO$ while $NB = 0.$ As time increases, $NA$ falls off exponentially, the number of atoms of $B$ increases, becomes maximum and finally decays to zero at $\infty ($following exponential decay law$).$

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