Talk:2775: Siphon

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My understanding was that siphoning can essentially be explained by the Bernoulli equation? There is a difference in potential energy between the upper and lower container so it flows. The weight of water in the downhill part of the tube pulls water up the uphill section of the tube (think like a vacuum), and so on until there's either no difference in head or no more water. Siphoning will work with any diameter tube. 15:43, 12 May 2023 (UTC)

That's right. The only mention of capillary action in the siphon wikipedia article is when talking about phenomenon that *isn't* a siphon. Barmar (talk) 16:15, 12 May 2023 (UTC)

Agree, capillary action does not seem to be referenced or implied in the comic, presenting only the (not "functioning") siphon phenomenon. 16:23, 12 May 2023 (UTC)

Seconded/thirded. Capillary action isn't even what they were expecting. The small amount of water in the lower recepticle indicates they correctly filled the tube, but then as the longer length drained it did not then induce further flow up and over through the shorter length. e.g. nature no longer abhored the resulting vacuum (or there was increased negative-pressure vapourisation, beyond that previously expected, or other method of seepage 'airlock'-breaking) and thus the short-end also drained straight back out again instead of becoming a potentially self-sustaining inflow to the whole siphoning setup.
If the upper end got restricted (say by touching the side of the bucket) the loss of flow would allow air to enter the bottom end and drain out the tube. I've done this. :-( RIIW - Ponder it (talk) 19:07, 12 May 2023 (UTC)
Indeed, even having an especially large diameter "tube" (/pipe etc) can allow air from the bottom to flow up to the peak & break the siphon effect. For reliable results, the lower end needs to be kept immersed or the hose needs to be relatively small in diameter. ProphetZarquon (talk) 14:11, 13 May 2023 (UTC)
While the capilliary action element could induce the start of a rather limited 'empty' siphon setup to start (maybe, I'd have doubts about the 'fluid friction' actually acting against the gravity-feed part, once the surface-tension bit has "climbed the mountain" and started to merely seep out of the other end, almost incidentally, for a sufficiently thin tubing where CA is a significant factor), this suddenly failing for whatever reason (surface-tension effects being nullified) wouldn't then send a token amount of water into the low bucket, nor particularly stop unrelated siphon-flow from continuing properly (in fact, suddenly 'interaction-free' liquid and tubing might siphon faster, with effectively zero fluid boundary effects dragging on the induced flow).
But perhaps someone with more QFD experience could explain where my assessment is wrong. So not going to personally rewrite the current Explanation intro just now. 16:21, 12 May 2023 (UTC)
I'd like to contribute as one more data point. I also don't see capillary action as being relevant. In particular, as another commenter said, the water in the lower bucket quite clearly supports the idea that the siphon effect was the subject of the characters' confusion. How else is Randall supposed to depict the siphon effect anyway? I agree that the drawing alone could also suggest capillary action is what's being investigated, but I don't think it suggests that the caption has incorrectly referred to it as the siphon effect. 18:44, 12 May 2023 (UTC)

Of course, if some physical law would actually stop working, people wouldn't be confused. They would drop dead. Due to physical laws working on level of elementary particles, every change would have lot of different effects ... and living organism live only thanks to being very carefully balanced in lot of regards. -- Hkmaly (talk) 20:49, 12 May 2023 (UTC)

Bug report 6EQUJ5: Odd signal emitted from Sagittarius constellation. Status: Closed - could not reproduce. 03:20, 13 May 2023 (UTC)

(I get that reference... :) However, launching off that to say: ) There's an old (short?) story... H.G. Wells era, possibly, but not him I think... where someone (who happened to be the first decent but amateur astronomer to get a cloudless patch of sky, one night) realises the Moon is in the wrong place, and the news then reaches (and troubles) the professional community who get a chance to observe/notice the change for the first fime and confirm it.. A 'glitch' seems to have passed through space and moved/retimed it, for a limited time, before it later snaps back to where (in the orbit) it now should be.
The trace of the glitch are seen further afield (implying a 'beam' of 'wrongness'), and ultimately it spawns something like Experimental Theology whereby observations of such clear "hand of the Creator" changes (implying we're essentially in a simulated universe being operated by a 'universal programmer', but in pre-computer terms) merge or muddy the boundaries between scientific rationalism (which clearly falls short) and religious philosophy (where undeniable 'proof' of something godlike is now suddenly an ironically confounding factor).
Cannot remember much about where I read it, I may be presuming some details about it that aren't actually there (even removing obvious mix-ups with similar brands of tale) and my Google-Fu fails to establish any obvious online reference to it (even just title+synoposis), so instead I'm setting down the 'spoilers' without reservation. 13:04, 15 May 2023 (UTC)

Siphoning is NOT because of capillary action! That should be changed!! 15:35, 13 May 2023 (UTC)

I guess I was wrong that siphons work because of capillary action. TianHanFei (talk) 1:57, 15 May 2023 (UTC)

As someone who's been publicly wrong here before, it can be stressful, but if it's any consolation, you're one of today's (probably much fewer than) 10,000: -- thanks for having a sense of humor about it Dextrous Fred (talk) 17:18, 15 May 2023 (UTC)

Potential inspiration

One potential source of inspiration for this comic is the Twitter account @Earth_Updates, which produces a lot of similar content. PotatoGod (talk) 19:54, 12 May 2023 (UTC)

I think if I added it to the article body it would get reverted, but the content seems very similar to how AI media produced delusional worlds for so many factions of people. It is not at all a big stretch to imagine people stepping into a metaverse or matrix where they aren’t sure what is real and physical laws match their intuition more than is actually correct. 08:23, 13 May 2023 (UTC)

Title text

Isn't the title text about stars like our sun rather than about plutonium? 00:55, 13 May 2023 (UTC)h

Seems to me unlikely that anyone would refer to stars as 'rocks'.Catherine (talk) 02:54, 13 May 2023 (UTC)
There is Slate that turn into lava spontaneously after lying around for thousands of years. I think the area they are in is called "Smoking Hills". There was recent research why that slate does this while in much the rest of the world slate is just flat, black rocks. I still believe this title text is about plutonium, though, as that slate produces so much heat, that one still hasn't managed to measure how hot it gets - but it produces that heat not for an near-infinite duration.--Gunterkoenigsmann (talk) 01:48, 14 May 2023 (UTC)
The only Smoking Hills that came to mind was natural shale-fires (chemical burning, and not hot enough for remelting to magma/lava.
Possibly there is a situation where it has done as you say (in some natural mass of rock, spotted somewhere in this planet's lithosphere, or elsewhere out there), but given the fine line between nicely sustaining and runaway chain-reactions, I'm not sure how easy it is for nature to 'engineer' a way to land on the middle ground and not go supercritical.
In order for accumulating ores to not just start a low-level fizzle (as above), over millenia, you might need separate ore-patches either side of a fault to come together in a suddenish techtonic slip, rather than a slow buckling of layers to increase effective ore-densities. And then you've got earthquakes, already, so not sure if the very low-grade nuclear explosion that is awfully close to being possible in this chance contrived example (at one end of the probability curve, unless U238 content is somehow preferentially leached out?) is going to be noticable.
But just hot enough for lava? If not already close to melting, anyway, under local temperatures and pressures? Not sure we've seen anything like it, even if it is technically feasible given enough happenstance setups by geology(/exo-geology), since planets formed. 09:16, 14 May 2023 (UTC)
Any sufficiently large rock containing sufficiently high concentrations of radioactive materials (such as the Earth) will partially melt. The energy is released slowly by decay not through fission. The large size ensures that the center is well enough insulate that slow heating accumulates until it reaches lava temperatures. The finite size ensures that enough heat leaks out that the magma does not become gas. 18:29, 16 May 2023 (UTC)

Title Text-Radiation

The title text is referring to the heat created by natural radioactive decay, not humans harnessing it in reactors.

The literal rocks of particularly radioactive elements still in the ground are constantly producing small amounts of heat without our assistance 06:27, 14 May 2023 (UTC)

Relevant xkcd:

Re:Actor: Siphon heat rocks water is the basis for my workflow. Randall please add a option, so siphon heat rocking can be re-enabled on demand. 19:23, 16 May 2023 (UTC) PicassoCT

siphon't 15:22, 13 May 2024 (UTC)