Two radioactive materials A and B have decay constants $25 \lambda$ and $16 \lambda$ respectively. If initially they have the same number of nuclei, then the ratio of the number of nuclei of B to that of A will be "e" after a time $\frac{1}{a \lambda}$. The value of a is _________.
Answer (integer)
9
Solution
$N_{A}=N_{0} e^{-25 \lambda t}$
<br/><br/>$N_{B}=N_{0} e^{-16 \lambda t}$
<br/><br/>$\frac{N_{B}}{N_{A}}=e=e^{9 \lambda t}$
<br/><br/>$t=\frac{1}{9 \lambda}$
About this question
Subject: Physics · Chapter: Atoms and Nuclei · Topic: Radioactivity
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