CUET · PHYSICS · PYQ PAPER 2023
After 4 hours, \( \frac{1}{16} \) of the initial amount of a certain radioactive isotope remains undecayed. What is the half life of the isotope?
- A 15 min
- B 30 min
- C 45 min
- D 60 min
Answer & Solution
Correct Answer
(D) 60 min
Step-by-step Solution
Detailed explanation
\( \frac{N}{N_0} = \left(\frac{1}{2}\right)^{\frac{t}{T}} \) \( \frac{1}{16} = \left(\frac{1}{2}\right)^{\frac{4 \text{ h}}{T}} \) \( \left(\frac{1}{2}\right)^4 = \left(\frac{1}{2}\right)^{\frac{4 \text{ h}}{T}} \) \( 4 = \frac{4 \text{ h}}{T} \)…
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