The next time you stand out in the rain, take a closer look at puddles and see if you can detect the “bounce” of raindrops. But first, to achieve a greater understanding of the dynamics of water droplets, watch this mesmerizing video, which shows in slow-motion what happens to droplets when they land on the surface of still water, and water that is vibrating.
This experiment was performed by scientists at the National Autonomous University of Mexico. It shows that water droplets will first bounce atop the surface and remain there briefly, then coalesce. But if the surface layer is vibrating–a loud speaker was used to create that effect in the experiment–the droplets will remain atop the surface water indefinitely.
The vibration creates a levitating effect. Beads of water will even cluster, and remain afloat together for as long as the surface layer is vibrating.
The scientists, Pablo Cabrera-Garcia and Roberto Zenit, used a dish full of tap water for the puddle and soapy water for the droplets. The addition of soap allowed them to use smaller droplets for the experiment.
Writes Esther Inglis-Arkell of the science website i09: “The added soap allows the drops to be small enough for the experiment to work. There is a size limit. Obviously an entire swimming pool can’t be kept bobbing on top of the other water.
“As the researchers add more beads, you can see them run along in lines, or bounce together in groups. It’s an amazing video!”
It is pretty incredible, whether you’re a science junky or not.