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NEET 1991 (AIPMT) · Law of Radioactive Decay

Law of Radioactive Decay question from NEET 1991 (AIPMT)

Q123NEET 1991 · AIPMTEasy

Law of Radioactive Decay

The half life of radium is 1600 years. The fraction of a sample of radium that would remain after 6400 years

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Answer: (d)

$n = \frac{6400}{1600} = 4$ half-lives.
Fraction left $= \left(\frac{1}{2}\right)^4 = \frac{1}{16}$ .
So the answer is (d) $1/16$ .

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