7D10.41 - Radioactive Decay Model

Code Number:
Demo Title:
Radioactive Decay Model
Radioactive Decay, Half-Life
Area of Study:
Modern Physics
Colored Water, Food Coloring, Beakers, Glass Tubes, Tygon Tubing, and Pinch Clamp.

The decay tubes are set up as shown. Fill the top tube with colored water. As the top tube drains the bottom tube will fill to an equilibrium point and then slowly drain. This demo should simulate the radioactive decay of a sample through half-life to non-radioactivity. The top tube may be held at the full level by putting a tygon tube and pinch clamp on top.

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Disclaimer: These demonstrations are provided only for illustrative use by persons affiliated with The University of Iowa and only under the direction of a trained instructor or physicist.  The University of Iowa is not responsible for demonstrations performed by those using their own equipment or who choose to use this reference material for their own purpose.  The demonstrations included here are within the public domain and can be found in materials contained in libraries, bookstores, and through electronic sources.  Performing all or any portion of any of these demonstrations, with or without revisions not depicted here entails inherent risks.  These risks include, without limitation, bodily injury (and possibly death), including risks to health that may be temporary or permanent and that may exacerbate a pre-existing medical condition; and property loss or damage.  Anyone performing any part of these demonstrations, even with revisions, knowingly and voluntarily assumes all risks associated with them.