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PhysicsMediumMCQ2025 · 23 Jan Shift 1

Q40.A radioactive nucleus n2 has 3 times the decay constant as compared to the decay constant of another radioactive nucleus n1 . If initial number of both nuclei are the same, what is the ratio of number of nuclei of n2 to the number of nuclei of n1 , after one half-life of n1 ? (1) 1/8 (2) 8 (3) 4 (4) 1/4

What This Question Tests

This question tests the application of the radioactive decay law to compare the number of nuclei for two different radioactive substances after a given time interval defined by the half-life of one.

Concepts Tested

Radioactive decay lawDecay constantHalf-life

Formulas Used

N = N₀e^(-λt)

T₁/₂ = ln(2)/λ

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