Foucault pendulum

This article is about the physics experiment and instrument. For the novel by Umberto Eco, see Foucault's Pendulum.
Foucault's pendulum in the Panthéon, Paris

The Foucault pendulum or Foucault's pendulum is a simple device named after French physicist Léon Foucault, conceived as an experiment to demonstrate the Earth's rotation. If a long and heavy pendulum suspended from the high roof above a circular area is monitored over an extended period of time, its plane of oscillation appears to change spontaneously as the Earth makes its 24-hourly rotation.

The pendulum was introduced in 1851 and was the first experiment to give simple, direct evidence of the Earth's rotation. Foucault followed up in 1852 with a gyroscope experiment to further demonstrate the Earth's rotation. Foucault pendulums today are popular displays in science museums and universities.[1]

  1. ^ Oprea, John (1995). "Geometry and the Foucault Pendulum". Amer. Math. Monthly. 102 (6): 515–522. doi:10.2307/2974765. JSTOR 2974765. Archived from the original on 2015-04-02.