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JEE Main202125 Jul 2021Evening ShiftPhysicsNuclear PhysicsActual

The nuclear activity of a radioactive element becomes 1 8 th of its initial value in 30 years. The half-life of radioactive element is ________ years.

Correct answer

0

Step-by-step solution

A = A 0 e - λ t A 0 8 = A 0 e - λ t ⇒ λ t = ln 8 λ t = 3 ln 2 ln 2 λ = t 3 = 30 3 = 10   years

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