Frequently Asked Questions
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This pendulum provides visual proof of the Earth's rotation. Designed by Jean Leon Foucault in 1851, it is called the Foucault (foo-koh) Pendulum.
Pendulum: a body suspended from a fixed point so as to swing freely to and fro under the action of gravity.
How does the Foucault Pendulum work?
The direction of swing is constant. Although gravity is pulling down on the ball and tension in the cable is holding it up, there is no force acting to change the direction of swing.
Why does it appear to be moving in a circle?
The Earth's spin is essential to life.
The Earth's spin contributes to the movement of ocean and wind currents, which in turn affect climate, weather, food production, and our everyday lives.
The pendulum's direction of swing does not spin with the Earth.
The pendulum is not a perpetual motion machine.
The pendulum is not a clock.
Now imagine yourself hovering above the equator.
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