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JEE Main20203 Sep 2020Morning ShiftPhysicsNuclear PhysicsActual

In a radioactive material, a fraction of active material remaining after the time t i s 9 16 . The fraction that was remaining after the time t 2 is :

Options

  1. A4 5
  2. B3 5
  3. C3 4
  4. D7 8

Correct answer

C. 3 4

Step-by-step solution

N = N 0 e - λ t     . . . 1 N ' = N 0 e - λ t 2 … . 2 from (1) & (2) N ' N 0 = N N 0 1 2 = 9 16 1 2 = 3 4 .

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