Foucault pendulum Foucault pendulum The Foucault pendulum ( ; ) or Foucault's pendulum is a simple device named after French physicist Léon Foucault and conceived as an experiment to demonstrate the Earth's rotation. The pendulum was introduced in 1851 and was the first experiment to give simple, direct evidence of the earth's rotation. Today, Foucault pendulums are popular displays in science museums and universities. The first public exhibition of a Foucault pendulum took place in February 1851 in the Meridian of the Paris Observatory. A few weeks later, Foucault made his most famous pendulum when he suspended a 28-kg brass-coated lead bob
Foucault pendulum vector diagrams observed in relation to the pendulum swing. At the North Pole the support-point of the pendulum swing is located on the axis of rotation of the Earth. No matter what vertical orientation is established by the plane of the swing, the relative velocity vectors of the Earth's surface on opposite sides and equidistant from the center point of the swing will be in opposition. The Earth turns underneath the plane of the pendulum swing that is established. The support-point of the connection turns with the Earth and is depicted as freely suspended above the Earth. The plane of the pendulum