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PhysicsEasyMCQ2022 · 28 Jul Shift 2

Q18.A radioactive sample decays 7 times its original quantity in 15 minutes. The half-life of the sample is 8 (1) 5 min (2) 7. 5 min (3) 15 min (4) 30 min

What This Question Tests

This question involves calculating the half-life of a radioactive sample by using the radioactive decay law and determining the number of half-lives that have occurred in a given time period.

Concepts Tested

Law of radioactive decayHalf-lifeNumber of half-lives

Formulas Used

N = N₀ (1/2)^(t/T₁/₂)

N/N₀ = (1/2)^n

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