What is the name of the effect where vibrating a powder causes larger particles to move to the surface. Why does it happen?
I’ve seen this numerous times with things like hot chocolate, where shaking the bag moves the sugar crystals on top of the cocoa, or with small pebbles in buckets of sand.
I’ve been looking for videos of what I mean, but I normally just get videos of cymatics, which is not what I’m referring to. The closest I’ve found is this video below, where larger solid chunks of sand can be seen getting pushed out of the rest on the left-hand side