Half-life of Radioisotopes

For a radioactive isotope we can define half-life 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

Half-life: Example A

A simple example exploring the number of nuclei left after a number of half lives.

Half-life: Example B

A slightly more complex mathematical example.

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