1. Tardigrade
  2. Question
  3. Physics
  4. A heavy nucleus Q of half-life 20 minutes undergoes alpha-decay with probability of 60 % and beta-decay with probability of 40 %. Initially, the number of Q nuclei is 1000 . The number of alpha-decay of Q in the first one hour is

Question Error Report

Thank you for reporting, we will resolve it shortly

Back to Question

Q. A heavy nucleus $Q$ of half-life $20$ minutes undergoes alpha-decay with probability of $60 \%$ and beta-decay with probability of $40 \%$. Initially, the number of $Q$ nuclei is $1000 $. The number of alpha-decay of $Q$ in the first one hour is

JEE AdvancedJEE Advanced 2021

Solution:

Total no. of decays in $60$ minutes
$=1000-1000\left(\frac{1}{2}\right)^{3}=875$
So, no. of $\alpha$-decay $=875 \times 0.6=525$