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Foucault's Facts

Greetings, my name is Leon Foucault. I am a French scientist who lived back in the 19th century, long before you were born. I wanted to prove that the Earth rotates, or spins around. So in 1848 I built a huge pendulum.

Illustration of Leon Foucault. Fun Facts About My Pendulum
My pendulum had a cannon ball that weighed 28 kilograms (about 60 pounds—that’s how much four bowling balls weigh). The cannon ball hung from a wire that was 67 meters long (about 217 feet—that’s how long 6 school buses are). I put sand under my pendulum, so I could see the pattern that it traced in the sand. After I built my pendulum, I was ready to test it out. I pulled the cannon ball to one side. When I released it, the cannon ball began to trace a straight line in the sand. After a while I noticed that the pendulum swung a little clockwise, and the straight line in the sand began to spread out and look like skinny flower petals. My experiment was a success! I was finally able to prove that the Earth was rotating
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