Same chapter3 marksDifficulty: Medium
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3 marksDifficulty: Medium
The half-life of a radioactive nuclide is 4 days. What fraction of a sample remains after 16 days, and what is its decay constant?
Original Khojo Papers practice question — not from a past board paper.
Answer
One sixteenth remains, and the decay constant is about 0.173 per day.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Sixteen days is four half-lives, so the fraction is (1/2)4 = 1/16. The decay constant is 0.693 ÷ 4 ≈ 0.173 day−1.
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