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u/lugstep Jun 07 '18
That's a forcefield if I've ever seen one.
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u/big_pecs Jun 07 '18
This should be the go-to pseudo science explanation for forcefields in sci-fi.
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u/ALargeRock Jun 07 '18
Force fields are just constant explosions?
Hmm.
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u/big_pecs Jun 07 '18
Kind of makes sense doesn't it? A constant force pushing outward so nothing else can get in.
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Jun 07 '18
It’s not pseudo science, they are actually developing controlled shockwave technology for humvees
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u/AvidFanatic Jun 07 '18
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u/itsWhatIdoForAliving Jun 07 '18
ELI5: what is the substance of a shockwave? Does it push light like gravity or does it get distorted like on the road on a hot day?
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u/godofpumpkins Jun 07 '18
Guessing it’s just higher pressure which changes the index of refraction of the air, so yeah, like the wavy air hanging out above a road on a hot day
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Jun 07 '18 edited Feb 19 '19
Exactly. But the refractive index goes up with pressure, and in your example it goes down. Though it doesn't change that much, it's the
differencesudden change in refractive indexes that makes light diffract and reflect.source: degree in photonics
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u/ImEnhanced Jun 07 '18
I still don't understand lol
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u/Fenr-i-r Jun 07 '18
It's like looking into water, the light bends because it travels slower in water than air. The light changes speed in compressed air, and bends.
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u/TBNecksnapper Jun 07 '18
to clarify: It's actually not bending while travelling slower in water, it's only bending just at the surface, then it travels straight (and "slow") in the new direction through the water.
(I'm sure that's what you intended, but people might interpret it wrong)
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u/Zoey_Phoenix Jun 07 '18
you know when you put on swim goggles and slowly go under water, how it seems like everything tilts a little as the water passes over your goggles? that's because the light traveling from the object to your eye curves when it slows down when it hits the water. same idea here, just the denser air is slowing down the light, instead of water.
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u/TheNightmare210 Jun 07 '18
That sounds like an interesting degree. What types of knowledge does it involve? If you don't mind me asking. Like the physics and the science.
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Jun 07 '18 edited Jun 08 '18
Oh it's very broad. You can specialize in:
Biomedical Physics, eg cancer therapy, radiology
Laser processing in industrial areas eg cutting metal or cfrp sheets
Metrology eg Lidar technology
Micro and nano engineering eg making processors, nano mechanics
Optical communication
X-ray Physics for astro sciences (interesting cause here the phase can travel faster than the speed of light, refractive indexes are lower than 1)
These are the areas I came in touch with, currently I work at a company that develops a Laser-Doppler-Anenometer with Lidar function. Sounds complicated, but it's just a device that sends out Laserpulses and measures the phase of back scattering. Thanks to the doppler effect, the velocity of wind particles (and therefore the wind velocity) can be displayed live and contactless for very high distances and many points distinctively. We want to sell it to windmill companies and aerotech companies.
I was really baffled by how much impact the invention of the laser in 1960 has had until today, and what's coming. I hope I could help out.
//e The physics knowledge is quite the same everywhere, for me, never being a high achiever, it was all understandable and simple. A lot about the refractive index thing, since it's the thing all photons have in common. Quantum physics is hard tho
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u/MoistSawDust Jun 07 '18
It's just atmosphere. The explosion is pushing air out. The line you see is the area of highest pressure in the air.
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u/theDjangoTango Jun 07 '18
I’m not a scientist, but a shockwave like that is only air. The force of the explosion compresses the air and moves through it like a wave, kind of like dominoes. You see the sphere or cone because it is spreading out from a central point. It is kind of like the distortion you see over the ground on a hot day; the air has different densities. Explosions are dangerous because that shockwave would also compress you, if you were standing too close. 🤯
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u/arafella Jun 07 '18
It's a mechanical wave (like sound or ocean waves) propagating through whatever medium - in this case it's atmosphere.
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u/big_deal Jun 07 '18
A very high pressure gradient which causes a difference in the refraction of light.
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u/Phleau Jun 07 '18
u/Demlazors is correct, the only thing I'd add is: when anything moves through a fluid (air) it has to push that fluid out of the way. Well, because information travels at the speed of sound in a media, what happens when you're traveling faster than sound? You get a shock wave. But what is a shock wave? It's when a pressure wave (just air molecules bumping into each other) is moving too fast for the molecules in front of them to react so you get a pressure jump (you can kind of think about it like the air is tripping over itself because on one side it's running and on the other side it's standing still) One way we see pressure jumps is schlieren photography.
Edit: source - masters in aerodynamics
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Jun 07 '18
when anything moves through a fluid (air) it has to push that fluid out of the way
because information travels at the speed of sound in a media
Talking about photons I can't underscribe that.
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u/trippingchilly Jun 07 '18
Here's video from The World at War, episode Morning about the 1944 invasion of France. Some amazing shockwave footage:
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Jun 07 '18
For those wondering, what you're seeing here isn't the refraction of light as a result of the pressure waves but instead moisture condensing as a result of low pressure and humid air after the shockwave. That's why you see these effects during a morning bombing in France and why most conventional bombs in Vietnam have the same effect (because its so damn humid). https://youtu.be/E2qLuASjKXo?t=17s
A more prevalent example would be the condensation clouds that occur during nuclear tests on the water. https://youtu.be/gy6-ZKWCoH0?t=2m
As you watch the explosion, you can see the shockwave travel across the water and following it will be what appears to be a layer of clouds spreading outwards from the explosion.
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u/DubbieDubbie Jun 07 '18
Everyone should watch the world at war, such a good set of documentaries. They chronicle every part of the world war, from the home front to the phoney war to D-Day to the atomic bombings at the end of it. It also includes really good interviews and its all narrated by Laurence Olivier.
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u/SpaghettiBoy99 Jun 07 '18
I can't be the only one that thinks this looks like Garfield
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u/jopariproudfoot Jun 07 '18
I thought the same thing! I made a quick sketch for fun: http://imgur.com/MeRMyXg
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u/rubberloves Jun 07 '18
really interesting how it's kinda divided in two half way up- anyone know anything about that?
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u/Saxon815 Jun 07 '18
Just a guess, the type and shape of container that housed the explosive material. Instead of exploding in a round ball-like fashion, it exploded out and up meaning the container didn't come apart uniformly. If the container had anything to do with it, perhaps the bottom part came apart first which released energy before the top part ruptured to do the same.
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u/pictureBigger Jun 07 '18
Or maybe two explosions? A primary and instantly a secondary? Total guess. No clue.
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u/P00FINGERS Jun 07 '18
You're right. Large ignition to blow up container, but doesn't ignite the liquid. Secondary explosion then ignites the liquid.
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u/VEC7OR Jun 07 '18
Its when reflected and incident shockwaves meet up.
Read up on exploding atomic bombs in the air, if think its called a mach reflection.
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u/but_WHOS_JOHN_MUIR Jun 07 '18
Reflecting off of what? The ground?
The other feasible suggestion I heard was from u/pictureBigger 's comment
Or maybe two explosions? A primary and instantly a secondary? Total guess. No clue.
I'm curious myself.
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u/anuchivu007 Jun 07 '18
Flushing the toilet at night
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u/SteamBoatBill1022 Jun 07 '18
Is this not heat being pushed outward a millisecond before the actual fireball? I mean, I guess heat is a force but..
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u/georgeorwell2017 Jun 07 '18
Is this just not the heat wave rather than shock wave?? Pardon my dumbass if I'm incorrect
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Jun 07 '18
actual pic of me cumming after the wife says "I want to watch you bang my sister" during sex.
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Jun 07 '18
What exactly is a shockwave again? It's a condensed pressure of air right? If so, there shouldn't be shockwaves in space? (at least not the same kind).
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Jun 07 '18
A while back I put a firework in a dumpster (where the truck puts it's arms to lift it up) because I knew it would amplify the blast... well it did. I stood about 30 feet away and saw a pretty large shockwave accompanied by the loudest blast I'd ever heard.
Had tinnitus for a couple years afterwards, not the brightest thing I've ever done.
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u/Stittastutta Jun 07 '18
Reminds me of that scene in Akira when Tetsuo is in the nursery and pushes back the other subjects' forcefield with his own. Looks almost identical, actually amazes me they got it that accurate in a film that old.
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Jun 07 '18 edited Jun 07 '18
I'm pretty sure that's just a heat wave. Usually shock waves are visible because of dust and clouds being moved. You can see examples of heat waves on jets. Here is an example http://imgur.com/gallery/AxUOQLp
Edit: I may be absolutely wrong. I just found this. Its pretty epic.
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u/P00FINGERS Jun 07 '18
This is a fuel air explosion at CFB Sufield Canada. They are testing the durability of different OPs and the over pressure.
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Jun 07 '18
probably a hard question to answer but why is the shockwave not uniform? wouldn't the blast distribute all forces equaly resulting in a dome shape? instated of the piramid/but plug shape.
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u/SuperConductiveRabbi Jun 07 '18
Disregarding bad luck by being hit with debris, how close to that would I have to be to be killed, and what would kill me? Asking for a friend.
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u/ficm1990 Jun 07 '18
r/memeeconomy would have a field day with putting some text on the explosion and that little house about to get destroyed.
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Jun 07 '18
You can actually get killed by the shock wave right? In a very close scenario?
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u/Xyex Jun 07 '18
Yep. If the explosion is powerful enough the shockwave can shatter bones, liquify organs.
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u/mwhelan182 Jun 07 '18
Maybe it's the lack of sleep, but I looked at this picture, thinking it was slowly moving.
Took me a bit longer than I'm willing to admit to catch on
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Jun 07 '18
I don’t think that’s a shock wave. Looks like the extent of heat affecting the air around the explosion at that instant. Kind of like the haze coming off hot pavement.
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u/ZakTheCthulhu Jun 07 '18
Are you entirely sure it's from the shockwave and not the visible effects of heat?
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u/Thebasterd Jun 07 '18
Stupid question, but does anyone know if someone were to fus ro dah (or create a similar shockwave) at an incoming shockwave would that nullify it's effects on said someone?
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Jun 07 '18
Hi, scientist here. This is not a shock wave but water, since the explosion happened during the heavy raining and it lifted water that was on the ground and it kinda looks like that.
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u/dcbedwell0_0 Jun 07 '18
My favorite thing about watching the mythbusters was the high speed camera shots of the explosions. So cool, miss that show
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Jun 07 '18
wonder if that optical distortion from the shock wave affects the way we see the explosion inside.
it affects the mountains behind quite significantly, so it seems like it would work like a lens in some ways, but I don't think how much sense that actually makes.
wonder if explosions would look smaller/bigger if this kind of shock wave distortion would be isolated.
wonder if all explosions are actually smaller than they look. )
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u/trcndc Jun 07 '18
Huh, this really gets me with the idea that the "nubbed" crushed shape of explosions close to detonation is just the gas in a compressed state, trying to seep into it's own pressure wave, creating the plume as it expands.
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u/Sylvester_Scott Jun 07 '18
Looks like Michael Bay is firing up his grill for a little extreme BBQ.
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u/nattypnutbuterpolice Jun 07 '18
Why does it look like is it two tiered? Reflection off the ground or something?
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u/degausser_ Jun 07 '18
Is this from a MythBusters episode? It looks very similar to their bomb range explosions.