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Nuclear Fission Demo - Uranium-238 to Lead-208

The yellow squares ar Uranium 238 atoms. The blue squares are Lead atoms that were created by splitting the Uranium atoms. The little red dots are alpha particles. When a alpha particle hits the center of a Uranium atom, the atom is converted to Lead, and two alpha particles are created.

When alpha particles go off the screen they are eliminated.

If the density of uranium atoms is too low then the reaction dies out. 2000 is a good number of atoms.
Clicking on the mouse will erase the screen.
The 'Transparent Lead' checkbox makes Lead atoms not absorb alpha particles. There is a very big difference in how fats the reaction goes depending on this checkbox.

By Richard Keene - rkeene@xmission.com

Feel free to copy this applet. Also see http://www.atral.com/U238.html for a very nice description of Uranium decay.