Determining the activity of radioactive sources in curies

Now let's consider two radioactive sources. One decays at a rate of 18.5 billion atoms per second, and the other decays at a rate of 74 billion atoms per second.

18.5 x 109 dis/sec -------------- 74 x 109 dis/sec

Can you determine their activities in curies?

If you said that the activities of these two sources were 1/2C and 2C, you were correct. It is fairly simple to determine the activity of a source when you know how many atoms decay per second.

With radioactive sources, we compare the activities of the sources in terms of gram for gram. The activity, in curies, of 1 gram of any radioactive source is known as its specific activity.

Please note that the decay rate or the activity of the radioisotope does not directly relate to how much radiation is produced. Different radioisotopes produce different amounts of radiation as their nuclei change. If you want to read more about this, you can read the material below.


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