1. Tardigrade
  2. Question
  3. Physics
  4. The half life of a radioactive material is 12.7 hr. What fraction of the original active material would become inactive in 63.5 hr.

Q. The half life of a radioactive material is $12.7\, hr$. What fraction of the original active material would become inactive in $63.5\,hr$.

Nuclei Report Error

Solution:

We use
$N=N_{0} 2^{-t / T}$
$\Rightarrow N=N_{0} 2^{\frac{63.5}{127}}$
$\Rightarrow N=\frac{N_{0}}{32}$
There total number of nuclei decayed will be $\frac{31}{32} N_{0}$

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