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I've got a question that's been puzzling me since I walked in yesterday afternoon from the rainstorm. Why do shoes squeak louder on polished linoleum when they're wet than when they're dry? (Seems like the wet surface would have less friction as the shoe moved across the smooth floor.) And what makes the acoustic wave? I'm assuming it's not the water molecules' screams as they're ripped from the tread.
- Celia (age 62)
This is something I've wondered about too. Here's a guess, which my more knowledgeable colleague, Steve Granick, thinks is likely to be about right.Maybe tiny air pockets are forced out (or pulled
in) to tiny cracks, and the water has
to sort of snap aside to let it happen. (That's partly based on things
I've heard about how Scotch tape works.) A very large number of little snapping events could make a squeaky sound. So it sort of is the screams of the water molecules.
Perhaps some reader can help confirm or modify this idea.
(published on 10/26/11)
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