Halflife
Halflife of Radioisotopes
For a radioactive isotope we can define halflife in two ways:

The time for the number of nuclei in the sample to halve

The time for the activity to fall to half its original level
Halflife: Example A
A simple example exploring the number of nuclei left after a number of half lives.
Halflife: Example B
A slightly more complex mathematical example.
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