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Feynman: How the train stays on the track FUN TO IMAGINE 7
Christopher Sykes

A short clip from the 1983 BBC series Fun to Imagine in which Richard Feynman explains how a train stays on the track. He covers the geometry of tapered wheels that steer the train back toward the center of the rails.
HN people link it as Feynman's charming and clear explanation of why train wheels are tapered, whenever trains, bicycles or steering come up.
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