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Léon Foucault: 2 ideas worth knowing

2 ideas from Léon Foucault, each explained in a minute and credited to the original work. Free on Savvy.

• A swinging weight in Paris proved the Earth turns

  In 1851, physicist Léon Foucault hung a 28-kilogram bob from a 67-meter wire in the Panthéon in Paris and let it swing freely. Over hours, its path appeared to rotate relative to t…

  — Léon Foucault, Foucault pendulum

• A swinging weight in a Paris dome gave the first direct proof the Earth spins

  Copernicus and Galileo had argued the Earth rotates, but no experiment had shown it directly. In 1851, Léon Foucault suspended a 28kg pendulum from the dome of the Panthéon and let…

  — Léon Foucault, Physical Demonstration of the Rotation of the Earth

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