Wikipedia:Reference desk/Archives/Science/2019 March 13

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March 13[edit]

Electrified water[edit]

A question inspired by Infra...

If, say, a generator room at a hydroelectric dam is flooded and live electrical equipment shorted by the water (like the turbine hall of the Hammer Valley Dam in this here video), wouldn't all conductive objects touching the water (metal barrels, stairway railings, generator casings, etc.) be electrified too? And in that case, wouldn't stepping and/or jumping on those kill you just as readily as actually stepping into the water? Also, in that scenario, if the generators were powered up and the plant connected to the grid (without first pumping out the floodwater), wouldn't that just compound the problem (as opposed to opening up a secret underground bunker for you to explore)? 2601:646:8A00:A0B3:4C6C:BBA:4ED1:76B8 (talk) 07:28, 13 March 2019 (UTC)[reply]

As with the question you asked here Wikipedia:Reference desk/Entertainment#Infra you have linked to a dab page. Since you are obviously asking about the video game I am not sure the science ref desk will be able to answer your question. Remember things that happen in a fictional world may or may not have a fact based explanation. MarnetteD|Talk 07:37, 13 March 2019 (UTC)[reply]
I was actually asking about what would happen IRL, not in the game. 2601:646:8A00:A0B3:4C6C:BBA:4ED1:76B8 (talk) 07:38, 13 March 2019 (UTC)[reply]
As I said the things that happen in the game may have no connection to real life - that is the nature of fictional games. MarnetteD|Talk 07:42, 13 March 2019 (UTC)[reply]
Which is exactly why it made sense for the question to be asked. --76.69.46.228 (talk) 04:54, 14 March 2019 (UTC)[reply]
Especially since at the time I was considering a possible novelization of Infra (if the devs agree, of course), and for that I would need a greater level of realism than for an actual computer game -- I wouldn't want some civil engineer to not-so-civilly take my book apart like Mark Twain (wrongly) did to Fenimore Cooper and say that I got all the civil engineering bassackwards! 2601:646:8A00:A0B3:D0F5:B883:F30B:650F (talk) 08:36, 16 March 2019 (UTC)[reply]

The videogame/hollywood concept of water being "electrified" and simply killing anything that touches it is overly simplified, bordering on being basically magic. Electricity flows between regions of high and low potential along all available paths in inverse proportion to the resistance along each path. That cannot be simplified down to "touch it and you die." That could be the case. But it depends on far too many factors to make a blanket statement. Someguy1221 (talk) 08:14, 13 March 2019 (UTC)[reply]

Also, large amounts of current flowing through a short circuit will generally trip a circuit breaker, removing the source of current from the space in question. – Jonesey95 (talk) 11:50, 13 March 2019 (UTC)[reply]
Not if the short is upstream of the first circuit breaker, which could be the case in a generator room.
There should be a big difference between the effect of dropping a running hair-dryer into one's own bathtub, vs. somehow dropping it into a lake, for example. ←Baseball Bugs What's up, Doc? carrots→ 15:55, 13 March 2019 (UTC)[reply]
  • Yeah, but as Someguy said, predicting the behavior in detail gets complicated. Suffice it to say that if a certain part of the water would be dangerous to touch, then a metal object protruding from that part of the water might very well be equally dangerous. Also, it likely depends on what other parts of your body are touching when you touch the live thing: current has to flow through you to do harm. I can't find a link to cite for it, but in one of the later seasons of Mythbusters they demonstrated that if you ever find yourself standing near a fallen power line, you can get in trouble just by walking with big strides, as the ground may be electrified unequally in different places. Shuffle away and your chances are better. --76.69.46.228 (talk) 04:54, 14 March 2019 (UTC)[reply]
Thanks! So the answer is "maybe, so better not even try"? 2601:646:8A00:A0B3:D0F5:B883:F30B:650F (talk) 02:03, 15 March 2019 (UTC)[reply]
  • Added to archive copy: I've just seen the Mythbusters episode again. It was "Electrified Escape", from 2018, and Wikipedia does not have a summary of it yet. They did not demonstrate unequal electrification of the ground near an actual high-voltage source; presumably this would be too dangerous to try. Instead they assumed unequal electrification and tested how it would be best to move across the ground if you had do. To do the test they used a conductive substance and electrified it from one side at low voltage, and wore a suit equipped with contacts all over, and electronics to detect the low voltage. The result was a simulated fatality, not even from taking a big stride, but just from an ordinary step. It was possible to advance by jumping repeatedly with both feet together, but it'd be easy to overbalance and fall flat on the ground. What was safe was to advance one foot just a couple of inches, then the other, and shuffle forward in this way as far as necessary. --76.69.46.228 (talk) 18:31, 30 March 2019 (UTC)[reply]
Speaking of video games vs. reality, just try to find a contractor who will build you a room with a floor made out of lava. And if you do find one, good luck trying to get OSHA approval for your facility. I'm just saying. --Guy Macon (talk) 17:24, 13 March 2019 (UTC)[reply]
Just tell him it's the latest hot thing. ←Baseball Bugs What's up, Doc? carrots→ 21:39, 13 March 2019 (UTC)[reply]
You'll lava rock melting systems. They're hot hot hot! Not for use on silicate rocks. Sagittarian Milky Way (talk) 22:57, 13 March 2019 (UTC)[reply]
Well, actually something of the sort has been available IRL for a long time. 2601:646:8A00:A0B3:D0F5:B883:F30B:650F (talk) 04:45, 15 March 2019 (UTC)[reply]
Robert Wysocki, perhaps? Wnt (talk) 23:45, 14 March 2019 (UTC)[reply]

Scarring during "alien encounters"[edit]

A "contactee" I know, who unfortunately has given up on discussing UFOs and aliens with non-believers, wrote: "I'll say this though - I have marks and scars I got on my body after being sexually pounced on by a female Reptilian entity in 'my dreams' back in 1981 [at the age of 13] - so that's interesting in and of itself. Plus the scars that I received during a series of UFO (Grey alien) encounters when I was 7 years old. That kind of convinced me to look deeper than the 'just a dream' stage of thinking."

A few quick Google searches show that other people report unexplained scarring after alien encounters, but don't turn up any debunkings. What are the typical mundane explanations for these sorts of scars? (The only one I can think of is that the encounter happened to take place right after an injury that caused amnesia or loss of consciousness.) NeonMerlin 16:07, 13 March 2019 (UTC)[reply]

"What are the typical mundane explanations for these sorts of scars?" What scars? HiLo48 (talk) 16:33, 13 March 2019 (UTC)[reply]
Psychosomatic lesions (i.e. actual body injuries caused by one's own mind) are a rare but existing thing: see Stigmata. It would also be possible for someone to make up a story, self-harm to create supporting evidence, then either maintain the falsehood or actually come to believe in it. {The poster formerly known as 87.81.230.195} 2.123.27.125 (talk) 16:40, 13 March 2019 (UTC)[reply]
I remember reading a book by Professor Platonov (in Russian) long ago. The book had a photograph of a second-degree burn to a subject's arm inflicted, it said, by a room-temperature coin which the subject thought was very hot. The original book is long lost, unfortunately; but I'll try to find the exact reference when I have time. Dr Dima (talk) 23:30, 13 March 2019 (UTC)[reply]
  • There was one case in the '90s (can't source it offhand, but I would have read it in the Fortean Times). Of someone reporting 'radiation burns' after repeated abductions.
It turned out they were indeed radiation burns. Infra red radiation, from an electric fire. They were making 'stencils', holding those in front of their arms and legs, then burning themself with the heat from the fire. Andy Dingley (talk) 16:51, 13 March 2019 (UTC)[reply]
The mundane explanations are just that - mundane. See here. We all have scars that we don't recall the exact origin of, but if we are primed to think that we've been abducted, we make a connection between two and present the scar as evidence. A similar example is discussed in our article on the Seattle windshield pitting epidemic. Matt Deres (talk) 17:50, 13 March 2019 (UTC)[reply]
Interstellar travels are impossible and UFO and aliens are a myth. AboutFace 22 (talk) 19:41, 13 March 2019 (UTC)[reply]
We can't say that with absolute certainty. ←Baseball Bugs What's up, Doc? carrots→ 21:40, 13 March 2019 (UTC)[reply]
You can't prove that anything except yourself exists with absolute certainty, however the odds that interstellar travelling aliens don't exist is as good or better as the odds that the world outside of your own mind exists. Which is good enough. --Jayron32 02:11, 17 March 2019 (UTC)[reply]
The best scientific information that we have is that the theory of relativity, which states that the speed of light is a universal absolute constant, accurately describes the universe. Interstellar travel is extremely difficult (although not impossible) if the theory of relativity is correct. We know that the theory of relativity is a very good theory. We also know that it isn't consistent with quantum theory, which is also a very good theory. Robert McClenon (talk) 02:50, 14 March 2019 (UTC)[reply]
Also, AboutFace 22 is making the unstated assumptions that if UFOs existed (beyond being mis-perceived mundane craft or phenomena) they could only be interstellar craft crewed by aliens. Other hypotheses have been proposed, such as time travelling craft or inter-dimensional craft, crewed by non-human or post-human sapient creatures native to the past, present or future Earth. etc. (NB: although interested in the social and psychological phenomena of such beliefs and hypotheses, I strongly doubt that any of them are correct.) {The poster formerly known as 87.81.230.195} 2.123.27.125 (talk) 17:57, 14 March 2019 (UTC)[reply]
  • Apart from the nocebo effect explanations above (which can cause quite physical symptoms), if someone claims to have been sexually assaulted by an alien/reptilian/etc. at age 13, actual sexual assault (by a human) is a hypothesis to at least consider. See trauma and false memory for the psychological factors at hand, see your conscience for whether and how to approach that situation with your friend, and see a lawyer for any kind of legal action. TigraanClick here to contact me 09:54, 14 March 2019 (UTC)[reply]
    Thanks; I've approached a third party about this possibility, since as a known skeptic, I can't approach the contactee directly and expect to be listened to. NeonMerlin 02:20, 15 March 2019 (UTC)[reply]

I have to think such injuries are common. I had one recently: I noticed a big scrape on my leg while showering (it healed normally). No idea how I got it but if it was alien abduction I'd hope I'd remember. So I shrugged it off. 173.228.123.166 (talk) 03:26, 16 March 2019 (UTC)[reply]

Does Pluto have less orbit period variation in solar system barycentric coordinates than heliocentric?[edit]

What about Neptune and Uranus? Sagittarian Milky Way (talk) 18:35, 13 March 2019 (UTC)[reply]

The Plutonian, Neptunian and Uranian years are 248, 164.8 and 84.0205 earth years respectively, regardless of the physical coordinates you choose. DroneB (talk) 11:52, 14 March 2019 (UTC)[reply]
They don't follow perfect 2-body problem ellipses. In fact Neptune was discovered from its perturbation of another planet's orbit at a tech level when only Mercury was close and fast enough for non-Newtonianess to be noticeable. Sagittarian Milky Way (talk) 13:30, 14 March 2019 (UTC)[reply]