A radioactive source has a half-life of 6 hours. What fraction of the nuclei remains after 24 hours?
Answer and explanation
Correct answer: A. 1/16
- Step 1: 24 / 6 = 4 half-lives. Step 2. Halve four times: 1/2, 1/4, 1/8, 1/16. Answer: 1/16. Why not the others: The others miscount the half-lives.
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