Kicker: The physics of squeak

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NICK EICHER, HOST: That high-pitched squeak is as much a part of the soundtrack of basketball as the referee’s whistle.

Now scientists say they finally know the mechanics behind it.

Researchers at Harvard slid basketball shoes across glass under high-speed cameras.

What looked like a smooth glide was anything but.

DJELLOULI: Squeaking is basically your shoe rippling… creating wrinkles that travel super fast… and they repeat at a high frequency.

The rubber sole sticks, slips, and snaps forward thousands of times per second.

Tiny earthquakes — the same physics as shifting tectonic plates.

Only beneath a shoe.

Now that engineers understand the mechanism, they can design for it — or against it.

How would stealth sneakers change the game?

It’s The World and Everything in It.

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