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JEE Main20211 Sep 2021Evening ShiftPhysicsNuclear PhysicsActual

The half life period of a radioactive element x is same as the mean life time of another radioactive element y . Initially they have the same number of atoms. Then:

Options

  1. Ax and y decay at the same rate always.
  2. Bx -will decay faster than y .
  3. Cy -will decay faster than x .
  4. Dx and y have same decay rate initially and later on different decay rate.

Correct answer

C. y -will decay faster than x .

Step-by-step solution

The formula of half-life in terms of the decay constant, t 1 2 = 0 . 693 λ x = 1 λ y ⇒ λ x = 0 . 693 λ y ⇒   λ x < λ y

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