1. Define ‘activity’ of a radioactive material and write its S.I.… - Vidyadip

Question

Define ‘activity’ of a radioactive material and write its $S.I.$ unit.
Plot a graph showing variation of activity of a given radioactive sample with time.
The sequence of stepwise decay of a radioactive nucleus is

If the atomic number and mass number of $D_2$ are $71$ and $176$ respectively, what are their corresponding values for $D$?

✓

Answer

The total decay rate $($of a sample$)$ at the given instant, i.e., the number of radionuclides disintegrating per unit time is called the activity of that sample. The $SI$ unit for activity is becquerel $(Bq)$.
Graph:

$72$ and $180$.

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