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Nuclei — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsNuclei3 Marks
Question
Consider a radioactive nucleus A which decays to a stable nucleus C through the following sequence:
A → B → C
Here B is an intermediate nuclei which is also radioactive. Considering that there are N0 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 ∞ (following exponential decay law).

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