eli5: Water droplets on makeup powder

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Can someone explain to me how these water droplets (I think??) hold together and combine with each other instantly?

In: Physics

Anonymous 0 Comments

The powder is hydrophobic, meaning that it doesn’t want to mix with water. That’s why it beads up into droplets. Water really likes to hold on to itself, and when it’s on a surface that doesn’t want to touch it, it will cling to itself. It wants to form little spheres, but because gravity is weighing it down, you get those lumpy droplets.

Because the powder doesn’t want to mix with water, it clings to the outside. You can see when they puncture it near the end that it has formed a skin around the interior water. That’s why the droplets can’t combine, because the skin is separating them. When enough pressure is applied to force them together, the powder is immediately forced outside the drop, forming a new skin.