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Area of Science: Physics Meant for Grade 7-9 (age 11-13). This experiment is inedible. An adult should be present. |
Overview:
Learn about surfaces that soap bubbles form
Equipment:
Glycerin, water, liquid dishwashing detergent, wire.
Safety:
Don't spill it on the rug or furniture.
How to do the experiment:
Make a 50-50 mixture of glycerin and water.
Add 5 % detergent. A couple of tablespoons to a cup of mixture. Exact
proportions are not crucial. Experiment.
Make wire frames of different shapes and dip in solution. If the
frames are twisted the bubbles will form minimum surface area
configurations. Try putting bubbles and films together.
Explanation:
The surface tension causes the surfaces to form minimum energy
surfaces. Very cool mathematics, very cool bubbles. The interference
of light gives rise to colors in patterns that change over time as the
films change witdth. See the book below for many other details.
Useful References:
"The Science of Soap Films and Soap Bubbles", Cyril Isenberg, Dover,
1992. $9.95 paper
Further comments: