Why are manhole covers round? - Marc Chamberland
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Why are most manhole covers round? Sure it makes them easy to roll, and slide into place in any alignment. But there’s another, more compelling reason, involving a peculiar geometric property of circles and other shapes. Marc Chamberland explains curves of constant width and Barbier’s theorem.
You saw that a collection of Reuleaux tetrahedra could be used to slide on; since they have the same width, the board stays level. Name two other three-dimensional solids on which a sliding board would stay level.
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Meet The Creators
- Educator Marc Chamberland
- Director Adam Comiskey
- Artist Clarrisa Hanekon, Ryan Flynn, Calvin Bacon
- Script Editor Eleanor Nelsen
- Narrator Addison Anderson
