Fb-3Soap Bubble Paradox
Published: Thursday 09 March 2006 - Updated: Tuesday 29 March 2011
To show that small bubbles have greater air pressure inside them than larger bubbles.
- Soap bubble solution
- Special glassware
- Watch glass
Click on pictures to enlarge.
a) Principle of physics illustrated
In a soap bubble the excess pressure is related to the surface tension and radius by
A bubble is blown in each of the two pipes with the communicating tap closed. The bubbles are blown of nearly equal size. When taps B are opened the small bubble gets smaller and blows out the larger one, showing that the pressure was lareger in the smaller bubble.