Difference between revisions of "Talk:2201: Foucault Pendulum"

Explain xkcd: It's 'cause you're dumb.
Jump to: navigation, search
Line 20: Line 20:
  
 
I don't think there's any indication that this comic takes place during a physics lecture. It's more likely that it takes place in a science museum, and this is a museum tour guide explaining the Foucault Pendulum to museum visitors. [[User:Ianrbibtitlht|Ianrbibtitlht]] ([[User talk:Ianrbibtitlht|talk]]) 00:16, 13 September 2019 (UTC)
 
I don't think there's any indication that this comic takes place during a physics lecture. It's more likely that it takes place in a science museum, and this is a museum tour guide explaining the Foucault Pendulum to museum visitors. [[User:Ianrbibtitlht|Ianrbibtitlht]] ([[User talk:Ianrbibtitlht|talk]]) 00:16, 13 September 2019 (UTC)
 +
 +
I don't know if it's still the case, but back in the 90s some Earth orientation work was very hush-hush military business. It turns out that really detailed models of how the Earth moves are important for targeting long-distance missiles. [[User:Dfeuer|Dfeuer]] ([[User talk:Dfeuer|talk]]) 02:35, 13 September 2019 (UTC)

Revision as of 02:35, 13 September 2019

I take it the pendulum is somewhere deep underground, which would shield Black Hat from the cataclysmic side effects? Besides, they have several backup pendulums that while not enough to maintain rotation are sufficient to slow the half enough to preserve life.108.162.212.149 20:11, 11 September 2019 (UTC)

I fear that the use of multiple pendulums to smooth out the catastrophy of stoping the Earth's rotation would probably just cause bits of the Earth to keep going and other bits to stop. Hey! That's plate techtonics! Obviously there are subtly dampened/purturbed pendula in secret (masonic?) temples all across the world, making all that happen! Someone likely pushed the one in Atlantis too far, one fateful day...
(BTW, the unsaid catastrophe element reminds me of a classic short story)162.158.154.31 15:29, 12 September 2019 (UTC)

If the pendulum could really affect Earth's rotation, Black Hat wouldn't need to stop the pendulum entirely; he'd only need to prevent its plane of oscillation from rotating. Another thought: if the pendulum and Earth's rotation were really bidirectionally linked somehow, there would probably be nothing Black Hat could do to alter the pendulum's plane of oscillation -- any more than he could alter the rotation of the Earth with just one human being's strength. That last thought doesn't seem to be the case within this story, though, or else the final frame's news report wouldn't have happened. Trueflint (talk) 20:46, 11 September 2019 (UTC)

Who says it's the energy from Black Hat's grab specifically? Maybe the magic pendulum just tells a device in the Earth whether or not the planet should be spinning, based on the current state of the pendulum. 172.68.46.167 08:15, 12 September 2019 (UTC)

Why does the description description Megan as a "professor?" She could just as easily be a teacher, a docent, a scientifically-interested parent, or just a random bystander. 11 September 2019

The sentence "It stays in a fixed plane while the Earth rotates under it." and the correspoding text in explanation are wrong. It would be true only if the pendulum was located on one of Earth's poles. Elsewhere, the plane in which the pendulum moves would still rotate with respect to its surrondings, but slower than on the pole. The rotation speed is proportional to the sine of latitude. At the equator, the plane would stay fixed with respect to its surroundings. See Wikipedia.--162.158.93.207 23:45, 11 September 2019 (UTC)

As a Physics teacher, I strongly support this. The fact that a Foucault's pendulum is keeping its oscillation plane constant with respect to an absolute reference frame is a common misconception, it should be mentionned as frequently as possible.--108.162.229.48 09:17, 12 September 2019 (UTC)

The Foucault Pendulum in this comic strongly resembles the one in the Franklin Institute in Philadelphia (both in shape and the way it is knocking over the pegs). Perhaps this should also be noted in the trivia section?162.158.126.46 05:16, 12 September 2019 (UTC)

Then list *all* the ones it strongly resembles. Do you think Philadelphia’s is the only one with pegs? I think that is the usual presentation. 172.69.70.107 10:01, 12 September 2019 (UTC)
A Google search reveals that nearly all of them have a weight that looks like the one in this comic, and many of them have some sort of pegs to demonstrate the circular motion over the course of a day. To put the location of any of them in the explanation (as it is now) is probably not appropriate. If there is a significant one somewhere in the world (largest, oldest, etc), then maybe we could mention that specific one. Ianrbibtitlht (talk) 14:56, 12 September 2019 (UTC)

Do we have anything about resonance transfer being proportional to the difference in mass? 172.68.189.19 16:20, 12 September 2019 (UTC)

I don't think there's any indication that this comic takes place during a physics lecture. It's more likely that it takes place in a science museum, and this is a museum tour guide explaining the Foucault Pendulum to museum visitors. Ianrbibtitlht (talk) 00:16, 13 September 2019 (UTC)

I don't know if it's still the case, but back in the 90s some Earth orientation work was very hush-hush military business. It turns out that really detailed models of how the Earth moves are important for targeting long-distance missiles. Dfeuer (talk) 02:35, 13 September 2019 (UTC)