1Two things to notice first
Grains have sizes, and shaking opens tiny gaps
You only need two ideas. Watch each one:
Grains come in sizes
A pile can be all one size, or a mix of big and small. A big bead and a tiny bead sitting next to each other are still both just grains in the pile.
Shaking opens gaps
Each shake makes the whole pile jiggle and lift for a split second. In that moment, tiny gaps open up between the grains — then everything drops back down.
2Two kinds of pile
The matched pile vs the mismatched pile
Whether shaking mixes or sorts comes down to one thing: are the grains the same size, or different?
The matched pile
No grain is smaller than the gaps, so nobody can slip past anybody. Shaking just jumbles them.
The mismatched pile
The small grains fit through the gaps that open under the big ones — so they can trickle down where the big ones can't.
3Your turn — shake the jar
Turn the shaking up and watch the grains jiggle
Here's a jar with big coral grains and small teal grains all mixed up. Slide the shaking from gentle to hard and watch the whole pile come alive — feel how shaking just makes everything jiggle.
4Now run the real test
Same-size beads, or big-and-small? Pick one, then shake
This time you choose the grains. We'll shake your jar and a matched jar side by side, the exact same way. Pick the jar you want to test — then guess what shaking will do to it.
Guess before you shake
You shake a jar of mixed big and small beads, over and over. Do they blend together more, or sort into layers?