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The rate constant values for the decay of radioisotopes X and Y , used in radio-medicine are 0.05 ~h ⁻¹ and 0.025 ~h ⁻¹ respectively. In a hospital, at a time ' t ₀ ' the activity of a sample of X was found to be twice that of Y . The activities of the two radioisotopes will be approximately equal when the time elapsed is:

Options

  1. Atwice the half-life of Y
  2. Btwice the half-life of X
  3. Cequal to the half-life of X
  4. Dequal to 1 / 2 the half-life of Y

Correct answer

B. twice the half-life of X

Step-by-step solution

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