What is Foucault: Definition and 22 Discussions

Jean Bernard Léon Foucault (UK: FOO-koh, US: foo-KOH, French: [ʒɑ̃ bɛʁnaʁ leɔ̃ fuko]; 18 September 1819 – 11 February 1868) was a French physicist best known for his demonstration of the Foucault pendulum, a device demonstrating the effect of the Earth's rotation. He also made an early measurement of the speed of light, discovered eddy currents, and is credited with naming the gyroscope.

View More On Wikipedia.org
  1. C

    I On whether the motion of a Foucault pendulum bob is comparable to ballistics

    A recurring question is: while the motion of a polar Foucault pendulum is fairly straightforward, the case of a non-polar Foucault pendulum is quite difficult to visualize. In 2020, on physics stackexchange someone submitted that question and I contributed an answer. In a comment to another...
  2. H

    How can I design a Foucault Pendulum for my university building?

    Hi guys, I think I have persuaded the administration to install a Foucault pendulum in my university building where a high roof and open spaces are available. The thing is I have to project it with design, cost, etc. Those are domains which I don't have much expertise as a simple physicist. So...
  3. Z

    Foucault Pendulum Release Velocity in Spherical Coordinates

    If the pendulum on the North pole is released to start it via burning the separation string, (to avoid adding an additional tangental force), wouldn't the pendulum at the time of release, already have a tangential velocity? does that effect the outcome of the experiment ? since the plane of...
  4. L

    Misc. Can anyone suggest a suitable material for a Foucault pendulum platform?

    I'm about to pick up again on a project started last summer to build a Foucault pendulum that will fit on, or at least, above a desk in an ordinary room. This was described, with photographs in...
  5. xaratustra

    Foucault pendulum and a round globe

    Imagine we are all cavemen without satellite technology and just discovered the Foucault pendulum! As we know the angle of presession depends on the latitude. This can be used to prove that the Earth is rotating, right? Now by putting several Foucault pendula around the Earth, at equidistant...
  6. J

    I Connection between Foucault pendulum and parallel transport

    Hello! I try to think about the Foucault pendulum with the concept of parallel transport(if we think of Earth as being a perfect sphere) but I can't quite figure out what the vector that gets parallel transported represents(for example, is it the normal to the plane of oscillation vector?). In...
  7. whitsona

    Foucault Pendulum: How important is release mechanism?

    I built just a long pendulum in my house in order to start looking at a simple Foucault pendulum "prove the Earth moves" event at the science museum I'm helping to start here in Pensacola. It gave me a nicely reliable movement that seemed to show the pattern I was looking for. Every time, it...
  8. A

    Foucault pendulums -- ordering the part that connects the string to the ceiling

    Do you know where I can order a part that connects string to the ceiling? The part has to be rotate free with very tiny friction. Inside the part may be air filled or vacuum. There has to be no hard wired connection between the ceiling and the part. I would make one if I know how. Hope someone...
  9. D

    Foucault pendulum and angular momentum

    In a discussion with someone claiming to be a physicist (whether PhD or something less he did not say) we got into a hypothetical discussion related to Hitchhiker's Guide to the Galaxy. An alien civilization wants to move the Earth out of the way because it's impeding a galactic highway...
  10. G

    Single minded Foucault pendulum

    I have completed a bottom driven pendulum that seems to have a preference to swing E/W. It is a 10kg bob on a 6M wire. The pivot is a tungsten carbide pin resting on a watch jewel. No matter how I start it it precesses at exactly the correct rate for 32 degrees latitude then stalls when it...
  11. A

    Foucault pendulum string medium

    This question is literally driving me crazy. How does the String or rope or whatever is used in a Foucault pendulum not twist with the rotation of the Earth (because the rope is attached to bases that are attached to the ground). Actually if the bases are attached to the ground, that should...
  12. G

    Foucault Pendulum: Force & Motion Analysis

    This problem is about the Foucault pendulum. It is a mass, m, attached to a cable that does not restrict the motion. So it is sensitive to centrifugal and coriolis forces. The first part states that it has a potential ## V = \frac{m \omega_0^2}{2}(x^2 + y^2)## and to find the force associated...
  13. S

    Foucault Speed of Light Experiment

    In my class's set up of Foucault's design of the experiment to measure the speed of light, the light beam passes through a beam splitter but there is only one beam spot in the microscope. I'm confused as to why this is. Can someone help explain it to me?
  14. J

    Misunderstanding about the Foucault Pendulum

    Dear members, I have a misunderstanding about the Foucault pendulum. In early 1851, Foucault had an insight that led to his famous discovery. This bit of serendipity occurred during construction of a pendulum clock to regulate the drive of a telescope. Foucault had secured a rod in the chuck...
  15. GRB 080319B

    Foucault Pendulum: Proving Mach's Conjecture?

    https://www.youtube.com/watch?v=<object width="640" height="385"><param name="movie" value="http://www.youtube.com/v/aMxLVDuf4VY&hl=en_US&fs=1&"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed...
  16. G

    Foucault currents / Eddy Currents vs material selection

    Hello, I am a mechanical engineer by education and I am working on a multi disciplinary problem. I regularly work with eddy current dynamometers at work and I am curious about the materials used within the rotor and stator of these dynamometers. First off, this isn't a homework problem per...
  17. J

    Can the Foucault Experiment's Principles Be Derived Through Calculus?

    Hello The Foucault experiment is based on the non rotation of the oscillation plane of a classical pendulum. Maybe a stupid question but I'd like to know if there is a simple manner to derive it. By the conservation of angular momentum ? Thanks for your help...
  18. cepheid

    Foucault Pendulum: Exploring the Coriolis Effect

    Can somebody explain to me why it doesn't matter that whatever structure from which a Foucault Pendulum is suspended is also rotating along with the Earth? How come the pendulum's plane of oscillation is not altered? Wikipedia sort of has an answer, but to me it seems to amount to little more...
  19. J

    Coriolis and Foucault Pendulum

    I guess this question is very easy, but after it occurred to me, it has been torturing me for quite a while. I don't understand how the Coriolis effect and Foucault pendulum work. I thought everything inside the Earth was moving along with it (inertia). If we are in a moving train, and...
  20. L

    Foucault Pendulum - Lagrangian

    Homework Statement I should find the Lagrangian of a Foucault Pendulum in a coordinate system on the earth. That means L = T - V where T is the cinetic energy of the pendulum and V the potential energy. Homework Equations v' = v + [\omega, r] [,] denotes the cross productThe Attempt at a...
  21. D

    Understanding Foucault Pendulums

    Simple question - I'm having trouble conceptually understanding why the plane that a Foucault pendulum swings in does not rotate with the earth. I understand how the Earth turns under the pendulum, but isn't the pendulum rotating with the Earth when it's released?
  22. T

    Foucault pendulum - the physics and maths involved

    I have been looking at this paper (http://www.phys.unsw.edu.au/~jw/pendulumdetails.html) on the details of Foucault's pendulum. I am interested in understanding the details, but am having some trouble. My purpose is to study this as an example of how the analysis is done. I'd like to ask some...