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Airborne Viking posted:As other's have said, yes. Hell, given enough voltage, electricity will go "gently caress you" and arc through a vacuum. BattleMaster posted:It's not conduction when it's in a vacuum but it's electrons breaking free and travelling through space. It can happen at lower voltages if the metal is hot which was done on purpose in vacuum tube electronics and cathode ray tubes. It can also happen if the metal has a sharp point where the local electric field is strong enough to start pulling electrons off. We have switchgear at work that uses vacuum interrupters. The two electrical contacts are contained in a vacuum bottle so there is minimal/no arcing even if you are interrupting say 20,000 amps (fault) at 14kV.
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Aug 22, 2016 01:25
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BattleMaster posted:It's not conduction when it's in a vacuum but it's electrons breaking free and travelling through space. It can happen at lower voltages if the metal is hot which was done on purpose in vacuum tube electronics and cathode ray tubes. It can also happen if the metal has a sharp point where the local electric field is strong enough to start pulling electrons off. Even an ideal vacuum will breakdown and theoretically conduct under a ludicrously high voltage.
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Aug 22, 2016 01:31
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Three-Phase posted:We have switchgear at work that uses vacuum interrupters. The two electrical contacts are contained in a vacuum bottle so there is minimal/no arcing even if you are interrupting say 20,000 amps (fault) at 14kV. Great example here. https://www.youtube.com/watch?v=hIkNY5xjy5k Interrupting high-current, high-voltage flows is tricky because arcs are conductive so if your switch opens and there's an arc that means the switch is still effectively closed. Just opening the switch wider won't stop the arc. So what you've got here is 3 big air switches that swing open wide to keep the circuit open, one for each phase, and each one of those air switches is in series with two fast-opening interrupters that are designed to open at the same time to split the voltage stress between them and break the circuit with minimal arcing. Those switches are encased in bottles of sodium hexafluoride gas that will quench any arcs at that switch that do occur. So in this case, the rightmost switch in its bottle of SF6 fails. If you go through this frame by frame, you first see an arc flash across the middle switch in its gas bottle, because, since the switch it was supposed to operate in tandem with failed, the entire voltage was across that switch as it opened and so it arced. You can see that there's no arc across the right bottle, because it stayed closed the whole time. Ordinarily, after the two interrupters open, the air switch swings open, and the two interrupters close again so you have this big air gap keeping the circuit open (in frame-by-frame, you can see the arc across the one interrupter disappear when it closes again). But in this case since the interrupters didn't do their job there was still plenty of current flowing and there was that huge arc at the air switch, which would have kept going until it arced to ground or another phase if linemen weren't actually there at the time investigating a known problem.
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Aug 22, 2016 01:49
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dis astranagant posted:Even an ideal vacuum will breakdown and theoretically conduct under a ludicrously high voltage. Source?
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Aug 22, 2016 01:49
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Maxwells Demon posted:Source? Physics. Dielectric strength of a pure vacuum is on the order of a few dozen megavolts per meter, depending strongly on electrode material and shape. If you get a field strong enough that the field effect causes electron emission, those electrons will flow from the cathode to the anode just like in any other circuit; there's nothing in the way, after all. Phanatic fucked around with this message at 01:59 on Aug 22, 2016 |
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Aug 22, 2016 01:52
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Maxwells Demon posted:Source? Once you get a large enough voltage, you can get electrons to jump through the vacuum from one electrode to the other. That's not really conductance, though. What's more interesting is what happens once you get past the Schwinger limit. Essentially the electric field becomes large enough to spontaneously create electron/positron pairs, which act as charge carriers across the gap. Theoretically, of course.
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Aug 22, 2016 02:02
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Collateral Damage posted:It's like setting things on fire, you can set almost anything on fire if you try hard enough have a strong enough oxidizer I vaguely remembered this one from Ignition! but I don't think I remembered its byproducts. quote:Exposure of larger amounts of chlorine trifluoride, as a liquid or as a gas, ignites tissue. The hydrolysis reaction with water is violent and exposure results in a thermal burn. The products of hydrolysis are mainly hydrofluoric acid and hydrochloric acid, usually released as steam or vapor due to the highly exothermic nature of the reaction. OK, your poo poo's on fire and releasing acid in the form of steam when it hits water. The running shoe advice is looking better and better.
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Aug 22, 2016 02:04
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Jet Jaguar posted:I vaguely remembered this one from Ignition! but I don't think I remembered its byproducts. Yeah, ClF3 is hypergolic with basically anything that isn't a metal and leaves all kinds of fun and exciting chlorine and fluorine species in the process. And those metals aren't safe if something prevents them from forming a protective patina.
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Aug 22, 2016 02:10
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"Hypergolic with all known test-pilots" https://web.archive.org/web/20060218090235/http://www.flightjournal.com/articles/me163/me163_1.asp quote:2. Leaking fuel could turn pilots to jelly, particularly if the plane flipped over. http://www.ww2incolor.com/forum/archive/index.php/t-8093.html quote:According to the book Der streng geheime Vogel Me 163 by Major Wolfgang Späte (ISBN-13: 978-3895551420) an accident happened on December 30, 1943 at the former Rostrup airforce base at Bad Zwischenahn. A rocket piloted by Oberleutnant Josef Pöhs of Erprobungskommando 16 spun around during a skid landing and flipped, causing a fuel to rupture and the remaining T-stoff to spill into the pilot compartment.
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Aug 22, 2016 03:07
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C.M. Kruger posted:"Hypergolic with all known test-pilots" I like the part where their PPE only bought them a few seconds.
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Aug 22, 2016 03:13
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Sanctum posted:I fuel 737s and thanks for the nightmares. Jesus christ that takes getting degloved into a whole new level. What typically happens to dudes who get hit by a full on jet blast?
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Aug 22, 2016 03:43
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Volcott posted:What typically happens to dudes who get hit by a full on jet blast? High-bypass turbofan on ground idle will probably at worst knock you down, maybe roll you on the tarmac a bit. At full-throttle, well, change that to definitely knock you down and roll you around: https://www.youtube.com/watch?v=CpX1riSTeJc&t=174s If it's a low-bypass turbojet, that exhaust is going to be much hotter and if you're close enough you'll be scorched. There was an incident years ago with what I want to say was a Swedish Viggen, some bystanders had gathered on a hill to watch a takeoff, and to impress them the pilot passed very close over them in full afterburner and a number of them were badly burned.
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Aug 22, 2016 03:51
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Volcott posted:What typically happens to dudes who get hit by a full on jet blast? This https://www.youtube.com/watch?v=ZKIvFEe9KfE
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Aug 22, 2016 03:53
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Volcott posted:What typically happens to dudes who get hit by a full on jet blast? https://www.youtube.com/watch?v=MLB0qadBPwU&t=139s Edit: Haha, 3 different videos
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Aug 22, 2016 03:56
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A fourth video, showing precisely what the question was about : https://www.youtube.com/watch?v=J6yod-sOrT0
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Aug 22, 2016 04:10
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Aug 22, 2016 09:24
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Phanatic posted:Physics. Dielectric strength of a pure vacuum is on the order of a few dozen megavolts per meter, depending strongly on electrode material and shape. If you get a field strong enough that the field effect causes electron emission, those electrons will flow from the cathode to the anode just like in any other circuit; there's nothing in the way, after all. This is what I described but it's not really conduction. Things can't conduct if there's no charge carriers, and a vacuum has nothing in it to be a charge carrier. edit: I mean once current starts to flow there are electrons present and those are charge-carriers but they weren't there at first and originally belonged to whatever they were torn off of BattleMaster fucked around with this message at 11:12 on Aug 22, 2016 |
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Aug 22, 2016 11:04
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https://www.youtube.com/watch?v=SJWxQLXrO54 Here's the full video. It's actually an extended chase scene where he also sped through the automatic doors of the mall and drove on a pedestrian bridge. The driver wasn't the owner of the motorcycle and last I heard he still hasn't been caught, but they did identify the owner and impound the bike. The video was released by accident when it was uploaded to a video sharing website and they forgot to check the "Private" box. Which makes me wonder how many private videos are sitting on YouTube of poo poo like this.
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Aug 22, 2016 13:37
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Soviet OSHA
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Aug 22, 2016 17:12
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https://www.youtube.com/watch?v=08LOlZR4UN8
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Aug 22, 2016 17:30
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That went south real loving quick.
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Aug 22, 2016 17:33
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Theophany posted:That went south real loving quick. Funny in this context but totally puts into perspective how fast confined space dangers catch up.
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Aug 22, 2016 18:06
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Drowning.mp4
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Aug 22, 2016 18:28
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Yes, it's like a lava lamp.
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Theophany posted:That went south real loving quick. Well yeah, that's why people use it to commit suicide.
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Aug 22, 2016 18:28
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Crosspost from the terrible car stuff thread
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Aug 22, 2016 19:05
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How not to tie down your cargo: https://www.youtube.com/watch?v=hI04YcnrdAE
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Aug 22, 2016 19:44
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I'm glad russia is getting on board the whole artificial reef building bandwagon.
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Aug 22, 2016 20:18
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People in the comments joke it's a new, quick way to lay a gas pipeline.
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Aug 22, 2016 21:14
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Kurvi Tasch posted:How not to tie down your cargo: https://www.youtube.com/watch?v=38jDQkkaxT8 https://www.youtube.com/watch?v=W_dV9sjmdqQ https://www.youtube.com/watch?v=RrrDLdeL2HQ https://www.youtube.com/watch?v=VchsHhPIx_s https://www.youtube.com/watch?v=hvrgFPcPXfo And to bring this back around to the discussion of horrible elevator death: https://www.youtube.com/watch?v=54K1AgTKpbk&t=62s
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Aug 23, 2016 00:21
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haha it's even got the little old lady slowly shuffling for her life
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Aug 23, 2016 02:56
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Whose vodka-soaked idea was that?
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Aug 23, 2016 03:46
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Kurvi Tasch posted:How not to tie down your cargo: Yes, run towards the broken steel cables whipping through the air, guy at 1:36! There's no way would turn out badly!
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Aug 23, 2016 04:23
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VectorSigma posted:haha it's even got the little old lady slowly shuffling for her life her shriek as she notices the boat is the best
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Aug 23, 2016 04:40
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I'm watching Event Horizon and this spaceship is one giant flying OSHA hazard. Giant pits with no railings and the walls covered in spikes, slippery pools of liquid in working spaces, no safety overrides to prevent a crazy or malicious operator from opening the airlocks, insufficient spare carbon dioxide scrubbers, no PPE stations anywhere near the room containing the giant reactor that emits dangerous brain altering radiation. Also the ship keeps sending workers to a hell dimension.
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Aug 23, 2016 06:01
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drat that runaway anchor is terrifyingly awesome.
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Aug 23, 2016 06:01
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Sagebrush posted:Also the ship keeps sending workers to a hell dimension. Functioning as designed. Marked wontfix/closed
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Aug 23, 2016 06:03
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BattleMaster posted:Functioning as designed. Marked wontfix/closed So Google runs that ship?
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Aug 23, 2016 06:07
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The contractor I'm working for is very osha. Not pictured: The left ladder is sitting on a partially demo'd deck which is currently being held up by a piece of firewood. e:  The guard on that saw has long since been removed, of course.
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Aug 23, 2016 06:17
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Javid posted:The contractor I'm working for is very osha. This whole scene speaks of a man who is desperately trying to figure out what to do next and going with the first thing he thinks of, but never actually finishing the task at hand.
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Aug 23, 2016 07:21
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chitoryu12 posted:Whose vodka-soaked idea was that? quote:Whoever bought those cars signed a document allowing the cargo to be transported on the ship's deck at their own risk 
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Aug 23, 2016 08:19
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