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If you blow air through sand, it behaves like a liquid

posted by Jason Kottke   Sep 21, 2017

If you take a bin full of sand and blow air up through the bottom of it, the sand behaves like a liquid. The bubbles were freaky enough when I watched this for the first time, but when the guy reached in to submerge the ball and it buoyantly popped right to the surface, my brain broke a little bit. This video from The Royal Institution explains what’s going on:

Note that this is a different effect than non-Newtonian liquids (which are also very cool).

Update: Mark Rober made a hot tub-sized fluidized air bed: