Put your hands together for…
… Sandra Tsing Loh … with the Loh Down on Science! *clapping*
You know what that sound was? NOT my hands! Because that’s NOT EXACTLY how clapping works. What is it then?
Make some noise for Yicong Fu and team from Cornell University.
They put powder on their hands to see how the air moves when clapping. Then, they filmed it in slow motion.
And? It’s similar to what happens when you blow across a glass bottle. Sound waves bounce around a cylindrical hole, in this case between your palms. That ejects a stream of air and makes the clapping sound we hear.
Now, how about a round of applause for… physics!
Reference: Fu, Yicong, et al. Revealing the sound, flow excitation, and collision dynamics of human handclaps Phys. Rev. Res 7, 2025, https://doi.org/10.1103/PhysRevResearch.7.013259