Forming Liquid Marbles

05 Sep 2014

This high speed video shows a drop of water falling onto a bed of hydrophobic sand. Because the sand is hydrophobic (rather than hydrophilic, which is typically the case), the water expands across the surface of the bed rather than penetrating into the gaps between the sand particles. During this process, the particles become stuck at the air-water interface to leave a particle-covered droplet. Such droplets are often called liquid marbles. The video was shot at 6000 frames per second.