The half-life of a radioactive element is 5 days. After 20 days, the fraction undecayed is MCQ with Answer and Explanation

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The half-life of a radioactive element is 5 days. After 20 days, the fraction undecayed is

A. 1/8

B. 1/2

C. 1/16

D. 1/4

Answer: Option C

Solution (By JKExamLibrary)

4 half-lives => (1/2)^4 = 1/16.

This question belongs to: Science Physics

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