Suggests Earth's rotation.

Newton's first law. Useful Links: The California Academy of Sciences provides details on how to construct such a device, while the Smithsonian provides us with good information on how this amazing invention first proved that Earth rotates. Updated on: 06/13/13 Big Model at the Display Tower.

A model of a Foucault pendulum suggesting Earth rotation and pendulum vibration in a fixed plane.

Foucault pendulum device, variable speed motor

Rotate shaft from the motor drive setting the speed as low as possible. Pendulum oscillates in a fixed plane while hoop rotates.