Question

In one average life :

• A. half the radioactive nuclei decay
• B. less than half the radioactive nuclei decay
• C. more than half the radioactive nuclei decay
• D. all the nuclei decay

Answer 1

The correct option is C more than half the radioactive nuclei decay

As we know,
Avg. life time is $=1/k=1.44t_{1/2}$ higher than half life so more no . of atom will be dissociates.
Also,
$T=\frac{1}{\lambda }$
$N=N_0{e}^{-1/\lambda \times \lambda }=N_0{e}^{-1}$
$N=N_0\times 0.36$
64% of atom are decayed.