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9 Laws of Physics That Don't Apply in Hollywood
Ant writes "Neatorama lists nine laws of physics that don't apply in Hollywood (movies and television/TV shows). In general, Hollywood filmmakers follow the laws of physics because they have no other choice. It's just when they cheat with special effects that people seem to forget how the world really works..."
The "Hollywood special" from a few moths back.
I've always enjoyed intuitor dissect movie physics for some of the more popular movies.
http://www.intuitor.com/moviephysics/
That one bugged me about a recent Battlestar Galactica, as well. Inside the room, the characters were freezing because the air was leaking away. (Thus cooling the room.) I can accept that. But once they're blasted into space? Not a chance of freezing. No air for cooling == no loss of heat. (Actually, you can still lose it slowly through black-body radiation, but that's another topic.) Human skin is pretty good at holding pressure, so the big things are:
- Don't hold your breath (unnecessary internal pressure)
- Close your eyes (they're more susceptable to decompression)
See the research into the Space Activity Suit for more info.
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radium paint didn't glow because radium did... not in that concentration, or in those colors. the radium was mixed into a heavy coat of standard enamel with a whole bunch of phosphorescent pigments, which glowed.
until they burned out. old WWII radio dial markings from military gear have a lot of brown markings. they are radium paint with the phosphors all burnt out atomically, like a ghost image on a burned-in computer screen or monitor screen on an ATM. still radioactive and dangerous if ingested.
radium, polonium, radiocobalt, and other strong alpha emitters will emit a Czerinkon glow of blue when in the presence of hydrogen or water, which may be what you are thinking of. the blue glow is that of ionized hydrogen from the alpha hits, however, and should be thought of as a form of phosphorescence.
if this is supposed to be a new economy, how come they still want my old fashioned money?
When you sweat, the fluids come from inside your body. Since they're already heated, they will carry away some of the heat when they vaporize. So you'd probably die of other causes long before you overheated.
In the Space Shuttle, however, the bay doors are opened for heat rejection when in flight. Unlike the "cold" problem we see in Star Trek whenever they lose power (e.g. TNG: Booby Trap), they're far more likely to overheat due to the heat rejection systems being inoperable. (Presumably, a ship like the Enterprise would have a circulatory system that would pump heat from the inside of the ship to the outer skin, where it would be rejected as black body radiation.)
Javascript + Nintendo DSi = DSiCade
- None can love freedom heartily, but good men; the rest love not freedom, but license. -- John Milton
If you can't kill him with five shots, then you shouldn't be doing the job in the first place.
Don't forget that you want to use a lower grain count in your rounds, to reduce muzzle velocity. The last thing you need is the "pop" of a supersonic bullet giving you away. To compensate for the reduced muzzle velocity, use a bigger caliber to get the same stopping power.
So: large caliber, reduced power round, flash/sound suppressor on the barrel.
The man who does not read good books has no advantage over the man who cannot read them. - Mark Twain
On a related firearms note, they always f*** with the depiction of double action revolvers. When the actor checks to see if it's loaded, they release the catch and swing the cylinder out. They always spin it, and they always dub in the clicking sound of spinning the cylinder of a single action revolver (think cowboy Colt Peacemaker, where the cylinder doesn't swing out). In real life, they don't make any sound when you do that.
Some mornings it's hardly worth chewing through the restraints to get out of bed.
This is mostly due to the fact that Hollywood uses stage weapons, which have no projectile in front of the explosive. Having gotten to fire a whole plethora of movie weapons when working in theatre productions, I've seen these things up close. Without the projectile to provide back-pressure in the muzzle, the initial ignition which occurs at the back of the shell pushes the un-burned powder forward and out of the barrel where it burns as it escapes. This is what produces the huge muzzle flash in the movies.
Mind you, the weapons master also told me that they often add other things (corn starch, non-dairy creamer, etc.) to enhance the flash when they're shooting movies, because most directors like the effect so much.
In fact, most of the explosions that you see don't use gasoline any more either. Apparently non-dairy creamer produces a much better (and less dangerous to store) explosion. In fact, if you put a one gallon jug of non-dairy (powdered) creamer around a flash powder charge, you can get a 30 foot fireball. (My dad worked in pyrotechnics shows.)
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god damn people - Learn to use Mirrordot / CoralCache / Google Cache / WHATEVER
MIRROR
Actually, sweat works because the evaporation process is endothermic. When water turns from liquid to gas it consumes heat. That's why you can cool down to 98.6F even when its 105F outside. That's also why a room with a "cool mist" humidifier consisting of a fan and a sponge-like filter will cool down several degrees.
Moderating "-1, Disagree" is simple censorship. Have the guts to post your opinion.
This is possible. However, it takes time. For a raindrop the amount of inertia is very small as it has a small mass. For a bomb, it has a much higher inertia and as such it will take longer to lose a horizontal component.
Without resistance, the vertical component eventually might dwarf the horizontal.
However, if you look at a movie like Pearl Harbor you'll see planes dropping bombs straight down without any horizontal component at all. There's no initial velocity with is dwarved or diminshed. There is simply a straight drop.
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Wrong. As you sit in front of your computer, you exchange heat with your environment in three ways simultaneously: (1) conduction, (2) convection, (3) radiation.
The part you are referring to is heat transfer mechanism (1), conduction, as your body heats cooler air molecules around you. Mechanism (2), as occurs when those heated air molecules rise toward the top of the room making room for cooler ones, also requires air.
However, mechanism (3), the most effective of the three, does not require any medium at all. You, like all baryonic matter, emit electromagnetic radiation with frequencies and intensities as described by blackbody radiation, dependent on temperature. An object twice as hot gives of 16 times as much heat in radiation per unit time.
Normally, when sitting in front of your computer, you are radiating like mad, and so losing heat. However, so are the walls of your apartment. Those walls, being nearly the same temperature as you are, heat you to a large degree, making up for the heat that you are losing to radiation. Hence if, on a cold night, you are walking down a hallway in which one wall has a fireplace behind it, you immediately notice how warm the wall is without coming anywhere near it.
Considering that the "walls" in space are the 2.73K cosmic microwave background radiation, and that a person's temperature is more like 300K, you would radiate 10^8 times more energy than your receive. You'd freeze in a hurry.
Now, if there's a star heating you from one side, this can partially make up the difference. You still get the one-side-super-hot and one-side-super-cold problem, then, like the surface of Earth's moon writ small.
Trust me, CGI effects are absolutely up to scratch for explosions. I think it's more likely that those with plumes of black smoke are done on effects machines because that's what people expect, rather than using gasoline.
Explosions are actually rather easy, and the software somewhat cheap (see Particle Illusion for one such solution). One of the best showreels I have seen is Autodesk's. It goes to show that almost every work whose post-production goes further than clip rearranging and editing has effects of some sort; most of which you won't even notice.
Unless something is really wrong with the powder charge you're using in the gun, there shouldn't really be any "sparks" coming out of the end of the barrel, at least with modern smokeless powder.
The muzzle flash that comes out of a gun is superheated gas, the product of the powder's rapid combustion; a "spark" would indicate some form of burning / incandescently-hot large particles, and there really shouldn't be anything that big left after combustion. If there are big (enough to be visible) chunks of burning powder coming out the muzzle of your (modern) gun, you have some sort of problem. I'm not sure whether you'd even technically call a real muzzle flash a "flame," since it's not really burning anymore; the majority of the chemical reaction that launched the bullet, ran to completion in the first few fractions of a second after the primer detonated. On weapons with short barrels, the muzzle flash is visible because the exhaust gases exit the muzzle out into the atmosphere before they've had a chance to cool below the point of incandescence. I don't think there's really anything in the way of actual 'combustion' still going on.
Muzzle flash is another thing that Hollywood tends to exaggerate; although it's definitely an issue in real life, it's more difficult to see on a bright, sunny day than you'd expect from watching action flicks. FWIW, I think that they simulate muzzle flashes by using propane or methane, particularly for automatic weapons, in movies.
"Ladies and gentlemen, my killbot features Lotus Notes and a machine gun. It is the finest available."
It should probably be pointed out for those who have not handled firearms before that a .22 is not a certain kill, even at close range. They certainly can kill, but the movie weapons are often shot from across the room where -- were I a professional killer -- I would not trust to be a kill shot, let alone a clean "drop him" shot. Birds, squirrels and paper targets are a better bet.
"$30 for the One True Ring. $10 each additional ring!" -- JRR "Bob" Tolkien
Silent shotgun shells are much more effective and economical than noise suppressors. Not so good for sneaking up on people in crowds I suppose, but they are very effective (quieter than the mechanical noise of the action) and add no limitations to manually operated shotguns.
I would add that the author of TFA doesn't understand the physics of hand to hand combat very well. It is true that targets will not fly accross the room when kicked. In fact the better targetted the kick the less they will recoil. However, when kicking you are accelerating much of your body (hip, leg, foot) toward the target. The reaction has to overcome this momentum. Furthermore, if you use orthodox technique you have a connection to the ground specifcally designed to transfer the reaction through my musculo-skeletal structure into the earth (the emphasis on this base varies from style to style, but it always exists). In movies people are always jump kicking, but in real life that is of limited utility. You don't want to lose that connection to the ground unless absolutely necessary.
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I think the ammo you're talking about is not jacketed in steel, but cased in steel. And yes, some people believe it to be significant rougher on guns than conventional copper-cased stuff, but not because of the bullet going down the barrel proper, but due to the damage that the steel case may be doing to the chamber during loading and extraction.
.223 Remington chamber, as opposed to the 5.56mm "NATO Chamber" or the compromise "Wylde Chamber").
You used to find this stuff under the "Wolf" brand name, and it was mostly made in Russia and some other ex-WP countries. I think Wolf may be trying to move upmarket and has ditched the steel-cased stuff, recently though.
At any rate, the bullets in that stuff were pretty standard at least that I ever saw, but instead of using a brass case, as is used in most Western countries' ammunition, they went with steel cases, covered in some sort of paint and lacquer (assumedly for rust-proofing). There were a number of issues with it, particularly in close-tolerance weapons. First was just the threat of damage to the chamber because it's a harder metal (although I have doubts about this), more significantly was that if you blasted a bunch of it off rapidly, you could get the gun's chamber hot enough to start melting the lacquer off of the cartridges, and over time, build up a layer of lacquer inside the chamber, that would change its dimensions, and lead to feed problems, particularly if you switched back to other types of ammo.
I know a number of people who got burned by the lacquer-buildup problems, because they had AR-15 style rifles with tight-tolerance chambers (the
"Ladies and gentlemen, my killbot features Lotus Notes and a machine gun. It is the finest available."
So, when you see a gal kick someone across the room, technically, the kicker (or holder of a gun) must fly across the room in the opposite direction - unless she has a back against the wall.
Not only that, but it fails to take into effect the masses of the two individuals. Just like I could push, kick, or punch a ball away from me, a person with enough mass can in fact repel a person of smaller mass over a certain distance. Perhaps not across the room and partway through a wall, but most people could already figure that part out.
Still, whether it's a person or any other object, it all comes down to friction, angle, and mass. I semi travelling at decent speed can send a small car flying, especially if it manages to "scoop" it with a certain angle. A mid-sized person braces right can propel another person away, and a larger person (well, more massive) can do so to a greater extent.
As to the shotgun blasts blowing someone across the room, I've never shot anyone or anything at close range with a shotgun, but it might work against a smaller person/animal. With a really big gun held by a really massive person (properly braced) it would possibly stagger the shooter while propelling the shootee...