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OnDaFence 36M/44M
44267 posts
1/7/2019 5:21 pm

Last Read:
1/9/2019 12:53 am

Foucault



The fact that the earth rotates on its axis is common knowledge today, but until the mid-nineteenth century, it was merely conjecture. Earth's Rotation Day is being observed on January 8th The.French physicist Jean-Bernard-Léon Foucault, commonly known as Léon Foucault or Jean Foucault, is known for proving through his experiments that the earth rotates on its axis.



On January 8, 1851, Foucault performed an experiment in the cellar of his home, in which he swung a five-kilogram weight attached to a two-meter-long pendulum. He put sand underneath it to mark the pendulum's path, allowing him to see any changes in it. He observed a slight clockwise movement in the plane— (the floor ), and thus the earth, was slowly rotating while the pendulum kept its position. His experiment showed that the earth rotated on its axis. No longer was it just a hypothesis.



Shortly thereafter he demonstrated his findings. He sent out invitations to members of the French Academy of Sciences, and they attended a demonstration on February 3, 1851, at the National Observatory in Paris. Here Foucault showed his findings with an eleven-meter long pendulum.



France's President Louis Napoleon requested Foucault to make a public demonstration of his experiment. In March of 1851, Foucault suspended a twenty-eight-kilogram brass coated sphere filled with lead from a sixty-seven-meter wire. It was attached to the dome of the Panthéon in Paris. A pin was placed at the bottom of the sphere to better measure where it swung in relation to the plane. This pendulum fittingly became known as the "Foucault Pendulum." The results showed that the swing of the pendulum rotated 11 degrees clockwise in an hour, making a full circle in 32.7 hours. This first public demonstration brought large crowds, and interest in pendulums in Europe and the United States grew greatly after it.



Foucault determined that the amount of time that it took for rotation depended on the latitude of where the experiment took place. It took twenty-four hours for rotation at the poles, but it didn't rotate at all at the equator. It varied in time in the areas in between, depending on the distance from the poles and the equator.



Right here at the Science Center of Iowa we have a Foucault Pendulum for public viewing.



OnDaFence 36M/44M

1/7/2019 5:29 pm

HAPPY Earth Rotation Day!


OnDaFence 36M/44M

1/7/2019 5:30 pm

We'd be Really SCREWED If it DID'T!


OnDaFence 36M/44M

1/7/2019 5:34 pm

The rotation coupled with the the orbit around the sun's path would look more like a giant slinkie stretched into space.


OnDaFence 36M/44M

1/7/2019 5:35 pm

I LOVE Science & Technology when broken down to it's simplest pieces.


Hungr4Yungr 75M
5766 posts
1/7/2019 6:02 pm

Nice blog explaining the way the world goes round and round.
How long did it take you to paint the map on your hands? Good job!


bychance4709 61M

1/7/2019 6:57 pm

Science Center of Iowa has a Foucault Pendulum, who knew - not I, and I was born & raised, --hangs head in shame--


OnDaFence 36M/44M

1/7/2019 7:15 pm

    Quoting Hungr4Yungr:
    Nice blog explaining the way the world goes round and round.
    How long did it take you to paint the map on your hands? Good job!
I can't take credit for the world in my hands picture that is from the public domain. I had a great science teacher in school that made us think about the world and physics.


OnDaFence 36M/44M

1/7/2019 7:16 pm

    Quoting bychance4709:
    Science Center of Iowa has a Foucault Pendulum, who knew - not I, and I was born & raised, --hangs head in shame--
I seen it of a Science field trip in High School.really some cool shit there.


Spicy_D69 61M
514 posts
1/8/2019 10:47 pm

Have you seen the 2 at the Museum of Science and Industry in Chicago?


OnDaFence 36M/44M

1/9/2019 12:53 am

    Quoting Spicy_D69:
    Have you seen the 2 at the Museum of Science and Industry in Chicago?
Yes I have and the German Uboat too.