Define the $SI$ unit of radioactivity.
(N/A) The $SI$ unit of radioactivity is the $Becquerel$ $(Bq)$.
One $Becquerel$ is defined as the quantity of a radioactive material in which one nucleus decays per second.
Mathematically, $1 \ Bq = 1 \ \text{disintegration per second} = 1 \ s^{-1}$.
One $Becquerel$ is defined as the quantity of a radioactive material in which one nucleus decays per second.
Mathematically, $1 \ Bq = 1 \ \text{disintegration per second} = 1 \ s^{-1}$.
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