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MHT CET 2026 (19 Apr, Shift 1) · Law of Radioactive Decay

Law of Radioactive Decay question from MHT CET 2026 (19 Apr, Shift 1)

Q1MHT CET 2026 · 19 APR · SHIFT 1Easy

Law of Radioactive Decay

A radioactive sample has half-life of 55 years. The percentage of fraction decayed in 1010 years will be

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Answer: (c)

  1. Number of half-lives n=105=2n = \frac{10}{5} = 2.
  2. Remaining fraction =(12)2=14=25%= \left(\frac{1}{2}\right)^2 = \frac{1}{4} = 25\%.
  3. Decayed =100%−25%=75%= 100\% - 25\% = 75\%.
  4. So the answer is (c) 75%75\%.
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