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 D₂ 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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