Two-Balloon Balancing Act: Constructivist Teaching

by: Thomas O'Brien

This activity explores LaPlace’s law where membranes exert pressure on their contents that decrease as the membranes are stretched to larger sizes and their thickness decreases. The internal pressure of a spherical balloon is inversely proportional to its radius—as a balloon is inflated and its size increases, the internal pressure of the trapped gases decreases. The combined mass (but not volume) of the gases is conserved in this closed, two-balloon system. This provides an opportunity to investigate the nature of science via a cycle of predict-observe-explain.


Type Book ChapterPub Date 3/1/2010Stock # PB271X_8

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