A radioactive substance has half-life of 10 days. Fraction remaining after 30 days is MCQ with Answer and Explanation

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A radioactive substance has half-life of 10 days. Fraction remaining after 30 days is

A. 1/16

B. 1/4

C. 1/8

D. 1/2

Answer: Option C

Solution (By JKExamLibrary)

Number of half-lives = 30/10 = 3. Remaining = (1/2)³ = 1/8. Exponential decay N = N₀(1/2)^(t/T). Radioactive decay constant λ = ln2/T.

This question belongs to: Science Physics

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