Foucault Pendulum Precession

The Foucault pendulum is a simple pendulum that is free to oscillate in any vertical plane. The direction along which the pendulum swings rotates with time because Earth is rotating beneath it. The rate of this precession is proportional to the sine of the latitude.

Experiment

Use the interactive tool below to explore how the precession of the Foucault pendulum depends on the latitude. Change the latitude to observe the different precession rates in the Northern and Southern Hemispheres, and see what happens at the Equator and the poles.

1. Set the Latitude to 45 to see the pendulum precession in the Northern Hemisphere.
2. Set the Elapsed sidereal days to 0.25 and observe the unwrapped plane angle of approximately -63.64°.
3. Change the Latitude to -45 (Southern Hemisphere) and notice that the precession reverses direction to +63.64°.
4. Change the Latitude to 0 (Equator) and verify that the status becomes No precession.

Explore this interactive visualization fully at https://riano.app/module/foucault-pendulum-precession.