Q. In a sample of radioactive material, what fraction of the initial number of active nuclei will remain undisintegrated after half of a half-life of the sample
A) $\frac{1}{4}$
B) $\frac{1}{2\sqrt{2}}$
C) $\frac{1}{\sqrt{2}}$
D) $2\sqrt{2}$
Explanation
(c) $\therefore\frac{N}{N_{0}} = \left( \frac{1}{2} \right)^{t/T_{1/2}} = \left( \frac{1}{2} \right)^{1/2} = \frac{1}{\sqrt{2}}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.