The decay constant $\lambda$ of a radioactive sample is the probability of decay of an atom in unit time. Then,

  • A
    $\lambda$ decreases as atoms become older.
  • B
    $\lambda$ increases as the age of atoms increases.
  • C
    $\lambda$ is independent of the age.
  • D
    Behaviour of $\lambda$ with time depends on the nature of the activity.

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Similar Questions

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If a radioactive element having a half-life of $30 \ min$ is undergoing beta decay,the fraction of the radioactive element that remains undecayed after $90 \ min$ will be:

$Rn$ decays into $Po$ by emitting an $\alpha$-particle with a half-life of $4 \text{ days}$. $A$ sample contains $6.4 \times 10^{10}$ atoms of $Rn$. After $12 \text{ days}$,the number of atoms of $Rn$ left in the sample will be:

Explain the decay constant and write down its definition.

The half-life of a radioactive element is $30$ days. What percentage of the element will have decayed in $90$ days?

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