Come and see the rotation of the Earth: An exposition of Foucault's pendulum


Event details

Date 26.05.2023
Hour 09:3018:00
Speaker Cours SHS "Experimental history of science", Enseignant(s): Mihailescu Ion-Gabriel, Dumas Primbault Simon François
Category Exhibitions
Event Language French, English

Come explore one of the most remarkable experiments in the history of science: the Foucault pendulum. As part of the Master SHS course "Experimental History of Science", students reproduce in the MED hall the experiment performed by Léon Foucault in 1851.

  • The goal is to study the experiment and to be able to compare the opinions of the spectators almost two centuries later!
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Historical context:
In 1851, French physicist Léon Foucault demonstrated the rotation of the Earth using a simple pendulum suspended from the dome of the Pantheon in Paris. The experiment showed that the plane of oscillation of the pendulum appears to rotate in a predictable manner, providing evidence that the Earth rotates on its axis. This experiment revolutionized the way we understand the nature of our planet and its place in the universe. Foucault's Pendulum remains an important symbol of scientific inquiry and a testament to the power of experimental observation. So, join us on this journey and let's explore the fascinating history and science of the Foucault Pendulum.

The original experiment was done using 67 meters long rope and a 25 kg mass. As a result the pendulum was able to oscillate for more than 6h without too much damping. For this reconstruction we had to change the scale of the project to be able to fit it in this building. Here you can see a pendulum with a string of 6 m and a mass of 20 kg. This results in a shorter osciation period. The effect of the rotation of the Earth can be physically explained by the Coriolis effect, an inertial force acting perpendicular to the direction of motion in a rotating reference frame. In this experiment the oscillation plane turns at about 11°/hr. Stay here for 10min and you will be able to see the rotation of the Earth !

SHS course "Experimental History of Science"
As part of the SHS (Social and Human Sciences) program at EPFL, this course is aimed at master students in engineering, physics, chemistry, mathematics, life sciences, or computer science, who have almost no background in history or history of science. The first semester introduces the essential questions and insights in our field through lectures and “laboratory work”, deciphering hand-written texts, visiting the cantonal archive, examining and handling historical instruments from the UNIL-EPFL collection, reenacting alchemical experiments. In the second semester, students work in groups on a project concerning the reenactment of past knowledge creation (experiments, observations, drawings etc.). Students involved in the installation of the Foucault pendulum at EPFL: El Rawas Bassam, Gavignet Louis, Silvin Antoine, Suppa-Gallezot Valentin, Tambourin Noé et Ziadeh James

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