Richard Feynman Explains How Trains Stay on Track
BoreMeScience · Explainer · YouTube title: What keeps a train on the track?
Why it's here
HN links it as a great, surprising explanation whenever rail wheels, gauge or curves come up.
What it covers
A short clip of Richard Feynman explaining how a train stays on its tracks, through the conical shape of wheels and how it handles curves without differentials.