Radioactive decay to 1/32 initial: number of half-lives: MCQ with Answer and Explanation

Radioactive decay to 1/32 initial: number of half-lives:
A. 6
B. 5
C. 4
D. 3
Answer: Option B
Solution (By JKSSB Mock Tests)
(1/2)ⁿ = 1/32 ⇒ 2ⁿ = 32 ⇒ n = 5 half-lives. Exponential decay calculation. Memory aid: '1/2ⁿ remaining; 1/32 = 1/2⁵ ⇒ 5 half-lives'. Radioactivity arithmetic frequently tested in competitive exams.

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A fuse wire is made of an alloy of tin and lead because it has
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Correct Answer: Option A


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The loudness of sound is measured in
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Correct Answer: Option A


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A particle starts from rest and moves with constant acceleration. The distance covered in the first 3 seconds is 9 m. The acceleration is
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