A simple Java applet to demonstrate the exponential nature of radioactive decay.
(you will need Java installed in order to view the applet)
The program simulates 40,000 radioactive nuclei, shown in a 200x200 grid on the left. These all start off as undecayed (shown in red). During each timestep of the simulation, each nuclei is given a random chance to decay, simulated by a pseudo-random number. The nuclei are redrawn in black once decayed, and the total number of undecayed nuclei at each timestep are plotted on the graph on the right.
Download source code