This model simulates the spontaneous decay of a collection of radioactive nuclei. As they decay and become stable, the graph of the number that are left demonstrates the notion of "half-life".

For detailed instructions on using the program, take a look at the info window from the Decay model.

Download the StarLogoT source code for the Decay model:
Download decay

To run this file you need StarLogoT2002 for the Macintosh.
(download StarLogoT)

Click on one of the pictures to see a quicktime movie of the model:
Click on the left-hand icon to see a movie of Decay, and the right-hand icon for plots of the changes in radioactive nuclei and the decay rate over time.