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How To Build a Short Foucault Pendulum
KentuckyFC writes "Set a pendulum in motion and you'll inevitably give it an ellipsoidal motion, which naturally tends to precess. That's bad news if you want to build a Foucault Pendulum, a bob attached to a long wire swinging in a vertical plane that appears to rotate as the Earth spins beneath it. The natural precession always tends to swamp the rotation due to the Earth's motion. There is a solution, however: the behavior of the ellipsoidal motion is inversely proportional to the pendulum's length. So the traditional answer has been to use a very long pendulum (Foucalt's original in Paris is 67 meters long). Now scientists at Carnegie Mellon University have another solution (abstract). They've created a motor that drives a pendulum in a way that always cancels out the precession. That means the effect of Earth's rotation can be seen on much shorter pendulums such as the 3-meter pendulum on which they've tested their motor. That's just the start though. They say there is no limit to how short the new generation of Foucault Pendulums can be, and even talk about the possibility of tabletop devices."
A new generation of executive ball-clickers is born.
That sounds like a feat of engineering, not science.
At any rate, I'm sure the pendulum clock industry is ecstatic. Can I get a Ph.D. for building a motor to flip sand-filled hourglasses over?
A slashdotter who didn't build his own computer is like a Jedi who didn't build his own lightsaber.
When I was a kid I used to dream about having a tabletop Foucalt pendulum. My friends told me I was mad, and my parents tried to discourage me from thinking about it. "There's no such thing as a small Foucalt pendulum, Zouden! Maybe one day we'll take you to visit the one in Paris, but you'll never get to have your own one." Now, finally, my prayers have been answered.
"A week in the lab saves an hour in the library"
I live near the equator, you insensitive clods!
That's the most stupid thing I read in the last time... why do you need a FC in the first place if you put a motor into it...
It's like... showing that birds can fly by stuffing them into a cannon and fireing them upwards....