CUET · PHYSICS · PYQ PAPER 2025
If the half-life of a radioactive nuclide is 16 hours, what fraction of original sample will remain undecayed after 48 hours ?
- A \(\frac{1}{2}\)
- B \(\frac{1}{4}\)
- C \(\frac{1}{8}\)
- D \(\frac{1}{16}\)
Answer & Solution
Correct Answer
(C) \(\frac{1}{8}\)
Step-by-step Solution
Detailed explanation
\(n = \frac{t}{t_{1/2}} = \frac{48 \text{ h}}{16 \text{ h}} = 3\) \(\frac{N}{N_0} = (\frac{1}{2})^n = (\frac{1}{2})^3 = \frac{1}{8}\)
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