Surface tension causes the droplets to dance, kiss, and stride along flat glass surfaces. In the video, researchers Nate J Cira and Manu Prakash (Stanford) show off just what surface tension can do: it can sort different liquids automatically, cause droplets to chase one another in a circle, and much more. Check it out!
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As you can see in the video, researchers used water and propylene glycol to explore how fluid droplets will interact. The droplets’ motion may seem chaotic at times, but the researchers explained much of the droplets’ motion through the variations in surface tension between the droplets and their surrounding vapor.