Same chapter3 marksDifficulty: Medium
Distinguish between nuclear fission and nuclear fusion.
Radioactivity
1 markDifficulty: Medium
After three half-lives the fraction of a radioactive sample left undecayed is:
- a1/3
- b1/6
- c1/8
- d1/9
Original Khojo Papers practice question — not from a past board paper.
Answer
1/8
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Each half-life halves the amount, so after three the fraction is (1/2)3 = 1/8.
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