A radioactive substance decays to 1/16th of its initial activity in 40 days.

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A radioactive substance decays to 1/16th of its initial activity in 40 days. The half-life of the radioactive substance expressed in days is

Options

(a) 2.5
(b) 5
(c) 10
(d) 20

Correct Answer:

10

Explanation:

N/N₀ = (1/2)ⁿ

(1/16) = (1/2)ⁿ

n = 4

Half life = t / n = 40 / 4 = 10 day

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Topics: Radioactivity (83)
Subject: Physics (2479)

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