John Branch, a sports reporter at the Times, called on Sheila Patek for help understanding why basketball shoes squeak on hardwood. Patek’s work with spiny lobsters demonstrated how the animals rubbed their antennas on their heads, making a squawk that scared off predators. In the same way the bow of a violin “stick-slips” over the string, or a basketball shoe squeaks on a highly polished floor. In the last case it’s the corrugations on the bottom of the shoe that vibrate, not the medium they rub against. The sound assures players that they are traveling over the floor with just the right amount of grip: not so little that their feet slide out from under them, and not so much that they can’t turn quickly.
It’s an amazing world, in which the spiny lobster and LeBron James rely on the same mechanical principle!