American Journal of Physics
A soap bubble on the end of a cylindrical tube is seen to deflate as the higher pressure air inside the bubble escapes through a tube. We perform an experiment to measure the radius of the slowly deflating bubble and observe that the radius decreases to a minimum before quickly increasing. This behavior reflects the fact that the bubble ends up as a flat surface over the end of the tube. A theoretical analysis reproduces this behavior and compares favorably with the experimental data.
Jackson, David P., and Sarah Sleyman. "Analysis of a Deflating Soap Bubble." American Journal of Physics 78, no. 10 (2010): 990-994. https://aapt.scitation.org/doi/10.1119/1.3442800