CUET · PHYSICS · PYQ PAPER 2023
What will be the half life of a radioactive isotope whose \(\left(\frac{1}{16}\right)^{\text {th }}\) of initial amount remains unchanged after 2 hours ?
- A 60 min
- B 45 min
- C 30 min
- D 15 min
Answer & Solution
Correct Answer
(C) 30 min
Step-by-step Solution
Detailed explanation
\(N/N_0 = (1/2)^n\) \(1/16 = (1/2)^n \Rightarrow n=4\) \(T_{1/2} = t/n = 2 \text{ hours} / 4 = 0.5 \text{ hours}\) \(T_{1/2} = 0.5 \times 60 \text{ min} = 30 \text{ min}\)
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