A certain radioactive material can undergo three different types of decay, each with a different decay constant $\lambda_1$, $\lambda_2$ and $\lambda_3$ . Then the effective decay constant is

  • A

    $\lambda_{eff} =\frac{\lambda_1+\lambda_2+\lambda_3}{3}$

  • B

    $\frac{1}{\lambda_{eff}}=\frac{1}{\lambda_{1}}+\frac{1}{\lambda_{2}}+\frac{1}{\lambda_{3}}$

  • C

    $\lambda_{eff} =\lambda_1+\lambda_2+\lambda_3$

  • D

    $\frac{1}{\lambda_{eff}}=\frac{1}{3}(\frac{1}{\lambda_{1}}+\frac{1}{\lambda_{2}}+\frac{1}{\lambda_{3})}$

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