Question

Half life of a certain radioactive substance is $6$ hours. If you had $3.2kg$ of this substance in the beginning, how much of it will disintegrate in one day?

Answer 1

Given: Half life $=6hrs$
Total quantity $=3.2kg$
Total time $=$ one day
$=24hrs.=4$ half life.
We know $N=N_0{\left(\frac{1}{2}\right)}^n=N_0{\left(\frac{1}{2}\right)}^4$
$=\frac{N_0}{16}=\frac{3.2}{16}$
$=0.2kg$ left
i.e., it will disintegrate $=3.2-0.2$
$=3kg$. in one day