

How Physicists At Fermilab Build a Bridge - jdoliner
http://joedoliner.com/?p=36

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chrismear
That strikes me as an obvious and not particularly noteworthy solution.

Disclaimer: I have a Physics degree.

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ygvucoqwv
Remember these are physicists so this solution only came after they spent
hours trying to throw string across (you may neglect air resistance) float
string across (you may neglect the mass of the string) and jump across (assume
a spherical physicist in a vacuum).

The mathematicians came up with the string solution, but only after a few days
of attempting to drop the ball of string from the bottom to the top because
they had a different convention about coordinate systems.

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pbhj
I'd have expected the physicists to be first with the string theory. The
mathematicians should have spent at least one week discussing knot topologies.

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mwandel
Slight catch. if you suspend a rope pendulum from a horizontal string, if the
string flexes at all, it will essentially act like a longer pendulum
perpendicular to the string (where the string moves) than it does along the
string. The result is that the pendulum's swing has a different period along
either axis, and it will trace out a lissajous pattern, not a straight line in
its swing. And that sort of wrecks the idea of a focault pendulum.

Oops!

Better make sure your cable is REALLY tight.

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sound2man
If you can stretch a cable across a "chasm" chances are that you can pop an
I-beam in there instead. That would solve that problem.

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pbhj
Because I-beams are perfectly rigid and don't flex at all?? I'm guessing
"would render that problem so small as to be unnoticeable" but maybe the
pendulum is so light that effects are drowned by random noise or don't exist -
there must be a potential well to climb out of before lateral forces cause
axial flexing so I'm probably wrong.

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jdoliner
Another cute thing about Wilson Hall at Fermilab is that the front doors faces
precisely due north. Not because they were constructed with painstaking
precision but because the physicists have redefined Fermilab's coordinate
system such that north is defined as the direction Wilson Hall faces.

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quantumhobbit
If you every have a chance to visit fermilab, I highly recommend it. The
20-story pendulum is only one of many cool science geek things unrelated to
the accelerators you can see.

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pasbesoin
IEEE used to offer special tours. Don't know whether they still do.

