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Physics in the Movies 493

Posted by michael from the popcorn-throwing dept.
nucal writes "Here's a site rating Insultingly Stupid Movie Physics. A really thorough site with a rating system which ranges from GP (Good Physics) to XP (Obviously physics from an unknown universe)." My vote goes to the helix of M&M's.
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Physics in the Movies More

Physics in the Movies

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  • Crikey, yet another meaning for "XP" (Score:4, Funny)

    by IvyMike ( 178408 ) on Saturday June 15, 2002 @12:19AM (#3706405)

    Windows XP, eXtreme Programming, XPCOM, eXperience Points, "Cross Platform", and now this. It's got to be one of the most overloaded acronyms of all time.

  • Outrunning the sun (Score:3, Interesting)

    by fahrvergnugen ( 228539 ) <fahrv@hotmail.cDALIom minus painter> on Saturday June 15, 2002 @12:25AM (#3706430) Homepage
    They forgot about The Mummy Returns. As Roger Ebert points out in his Full review [suntimes.com]:


    4. I have written before of the ability of movie characters to outrun fireballs. In "The Mummy Returns," there is a more amazing feat. If the rising sun touches little Alex while he is wearing the magical bracelet, he will die (it is written). But Rick, carrying Alex in his arms, is able to outrace the sunrise; we see the line of sunlight moving on the ground right behind them. It is written by Eratosthenes that the Earth is about 25,000 miles around, and since there are 24 hours in a day, Rick was running approximately 1,041 miles an hour.


    • Re:Outrunning the sun (Score:5, Insightful)

      by Spock the Baptist ( 455355 ) on Saturday June 15, 2002 @01:22AM (#3706594) Journal
      Arrrrrgh! No! no! no!

      Mr. Ebert confused the speed of the shadow of an object on Earth with the speed of the Earths Terminator.

      Here's my e-mail to Mr. Ebert...

      Mr. Ebert recently wrote in his review of THE MUMMY RETURNS:

      "4. I have written before of the ability of movie characters to outrun fireballs. In "The Mummy Returns," there is a more amazing feat. If the rising sun touches little Alex while he is wearing the magical bracelet, he will die (it is written). But Rick, carrying Alex in his arms, is able to outrace the sunrise; we see the line of sunlight moving on the ground right behind them. It is written by Eratosthenes that the Earth is about 25,000 miles around, and since there are 24 hours in a day, Rick was running approximately 1,041 miles an hour."

      Mr. Ebert is in error.

      Mr. Ebert has over-simplified the geometry, and physics of the velocity of shadows generated by the Sun.

      While it is true that the Earth's rotates with an angular velocity of ~7.29e-5, and thus has a tangental rotational velocity of ~1041 mph, it is manifestly untrue that a shadow cast by mountains, canyon walls, etc. also travel at 1041 mph.

      The velocity of the shadow is a function of not only the Earth's angular velocity, but also of the hight of the object, the time of day, as well as the time of year.

      Consider the shadow cast by a flag pole. The length of the shadow is infinite at sunrise, but at local noon it will be at minimum at local noon. If the pole is located along the equator, and it's an equinox the the shadow will have a length of zero. Thus in six hours the shadow will have gone from infinitely long to infinitely short, thus having an average velocity that is infinite. (It is written by Zeno of Elea) A second example may serve to make my point a bit better. Consider the same day, and the same flag pole, but this time let us stipulate that the flag pole is 100 feet tall. As 09:00 local time the Sun will be 45 degrees above the horizon therefore the shadow will be 100 feet long as the oppsite, and adjacent sides of a 45 degree right triangle are equal. Thus, in the three hours between 09:00, and 12:00 local time the shadow of the flag pole will have moved 100 feet. Thus, the average speed at which the shadow will move in this period will be 100 feet / 3hours = 33.33... feet per hour, or ~0.0063131313... mph. Manifestly, this is very much less that 1041 mph.
      • Was he out running the Earth's shadow (sunrise) or running toward some object with a shadow... why would you run away from an object with a shadow if you're worried about the sun? and wouldn't he be vulnerable regardless of shadows? which the sun still penetrates with reflected light? thus he must have been running ~1041 mph.

        nice equations but you missed the point i think.

      • ...and 4,000 year old mummies coming back to life is completely realistic...

  • The Force violates conservation of momentum (Score:2, Funny)

    by Anonymous Coward
    Each time a Jedi uses the force to move an object, the Jedi doesn't seem to be subject to an equal and opposite reaction (Newton 3rd Law). Therefore conservation of linear momentum isn't conserved in the Star Wars universe. I think this can be bad for the universe.
    • Star Wars has some strange physics. For example, 'Light Speed' makes a trip to Tatooine seem like a a weekend camping trip.

      Just to tweak the people who take SW too seriously (they read the books, and the books tried to patch up obvious flaws in the script...), I came up with a theory that the Star Wars galaxy is scaled down to about 1/3rd of a lightyear wide. (Remember the galaxy in MiB?)

      You'd think they'd be receptive to this idea, afterall it explains a lot of strange physics in the movies. (Like people falling from 30 feet without injury...) It even gives motivation for the Force to 'surround all life forms'. Nope, it created contraversy.

      You see, SW fanatics think that the Empire could wipe out the Federation in Star Trek. If a Star Destroyer is virtually microscopic, it cannot possibly fight the Enterprise.

      Amusing, isn't it?
      • "I made the Kessel run in less than twelve parsecs"

        How's that for Star Wars and bad science?

        There is in one of the non-canon books somewhere an attempt to explain that line by saying that hyperspace is about well you can shave distance off a trip and therefore Han's statement in A New Hope is not pointless. I prefer to think that Lucas doesn't know what he is talking about.
      • Also it was funny to see the screwed up physics model they used in the star wars spece fighter scenes.

        In reality you will not be able to hear the laser guns firing on another ship or the screech of its engines as it files by, and you will not be able to hear the death star explode. This is of course because space is a vacuum and sound does not travel through it.

        • "In reality you will not be able to hear the laser guns firing on another ship or the screech of its engines as it files by, and you will not be able to hear the death star explode. This is of course because space is a vacuum and sound does not travel through it"

          I dun particularly care much for the whole 'sound doesnt travel in a vacuum' blooper. It's not a blooper. It's a fact of entertainment: Audio is more important than video.

          I do find it funny that you brought that up, though. I remember an Ep of Babylon 5 where one of the characters claimed to have heard the distinctive sound of a Shadow ship fly by. Heh.

          Oh oh there's another B5 physics blooper: Some dude kiled another dude and threw his body out of an airlock or something. Gera-baldy (Bruce Willis's little brother) claimed to have found the body clinging to the hull of the station. I'm reasonably sure that their spinny thing would have flung it off.
          • I do find it funny that you brought that up, though. I remember an Ep of Babylon 5 where one of the characters claimed to have heard the distinctive sound of a Shadow ship fly by. Heh.

            I recall that the sound often has a strong telepatic element to it. They may just be offering us a bit of the sixth sense there.

            Why not pick on the selective use of jump engine recharge delays instead?
          • In 2001, Kubrick uses the "no sound in a vacuum" fact to amazing effect. The 2 scenes that stand out in my mind are when Dave picks up the body using the pod's claws (you really get the sense of weightlessness from the silence) and again a few minutes later when Dave comes in through the emergency airlock: the explosion, him thrashing about, etc are all silent until the airlock finally closes, at which point you get the rush of air and the tension can ebb away.

            OK, so some people think 2001 is *way* too boring and slow to count as entertainment. But for me it shows that if you want the sound of an explosion, put the camera somewhere where it can be heard, don't just cheat and dub the effect on afterwards! I want to feel like I'm *in* the film, not just watching it...
        • sound in space -> this seems to be greatest problem with space movies at all. but i believe there are gadgets (THX certified of course) on the ships or in the ears, that scan the surrounding and give an audio-feedback, so that humans could behave in outer-space--traffic like on earth.

          but what really makes me thinking is why nobody complains about all the conversations with aliens in english! okay, on star trek there's a 'universal translator' and in another movie you've to swallow a pill with nanobots, which will do the translation. but why do they use the same frequencies and human-language for conversation?
          but why bother about the right sound? i'm sure they've all a sony space amplifier, 'cause sound is so essential for flying a spaceship and in battles!

          and can anybody explain to me, why all the spaceships (at least in star trek) just use 2 dimensions for flying around? when ships meet, they're always on the same level with the same orientation. and the energy waves (i.e. when a planet explodes) are more like a wave on a lake and no sphere. so the ship always tries to fly away and never uses the z-axis!

          ---
          on /. nobody knows, that you're a god!

          • Re:The Force violates conservation of momentum (Score:2, Funny)

            by Anonymous Coward
            My pet peeve about the SW movies:


            R2-D2 has got billions of gadgets built into him: Fire extinguishers, jets, everything. BUT HE CAN'T SPEAK ENGLISH! WTF?

          • Actually, IIRC there was an episode of one of the Star Treks where Quark, his brother, and his nephew crashed a spaceship after travelling back in time and space to Earth, in 1947. Yep, they were the Roswell crash.


            When the scene was shot POV aliens, they were speaking English, and had translators implanted in their ears so they could understand the scientists. When a scene was shot POV scientist, the aliens were speaking in a wierd babbling language (oddly reminiscent of "cut-up" sampled english, like they do to bad language in rap).

      • actually, Han Solo clearly gives a hint on SW Physics in 2 points:
        1) "...Jump to hyperspace..." There not traveling "light speed" there travelling in an alternate space.
        2)Kessel Run in 1.2 parsec. Everybody assume its a mistake, I never believed its a mistake. I also believed Kessel Run was some "flat space" distance, say 10 parsecs, but the challenge was to complete it by traveling the shortest distance in real space. so by traveling in hyperspace, you can travel a shorter distance then in "real space"
        Imagine bending space, ot a worm hole.
        I came up with that in 1977, when everybody was boohooih the parsec "mistake".
        Now, perhaps Hyperspace is an alternate universe that is smaller, so you punch into the alternate universe, travel some distance, then come back to this univers and you may have travelled 3 time the ditance.
        NO, I am not a star wars fanboy, but I used to be. Fortunatly, getting beat up with several movie release to video, each a little better then before, then realesing the stinker as ep 1, I'm not much of a fan anymore.The fact that I have yet to see ep2 astonishes some of my long time fans.
        • "1) "...Jump to hyperspace..." There not traveling "light speed" there travelling in an alternate space."

          Heh okay, I'll bite: ESB uses the term 'light speed' at least 3 or 4 times. In ANH, Solo says that they exceed the speed of light. By that definition, 'hyperspace' would be how they actually break the light barrier.

          Now normally I'd accept your explanation, except for a fatal flaw in ESB: The hyperdrive in the Millineum Falcon doesn't work until the very end of the movie, yet they traveled from one star system to another before the Empire could nab them. (And before they grew old and died.)

          This is what lead me to the 'mini galaxy' theory. There's no possible way they could travel inter-stellar without an FTL drive.

  • Hey! No fair! (Score:5, Funny)

    by philovivero ( 321158 ) on Saturday June 15, 2002 @12:40AM (#3706474) Homepage Journal
    They give the coveted GP == Good Physics award to Seven Years in Tibet...?!?! Like... okay? How about we give other coveted Good Physics awards to Lolita, Joy Luck Club, Pi, True Stories, and Office Space since they were so full of projectile cars, falling, laser beams, and other physical effects that could be modelled poorly???

    Then they go and say the Matrix had questionable physics, despite the fact that a key element of the plot is that the physics of the world are simply rules in a computer which Morpheus so eloquently describes: "some can be bent, others broken."

    I'm gonna just have to go ahead and disagree with you there.

    • Re:Hey! No fair! (Score:5, Interesting)

      by Lemmy Caution ( 8378 ) on Saturday June 15, 2002 @12:56AM (#3706523) Homepage
      You didn't actually click on the specific film reviews, did you?

      7 Years In Tibet had a very accurate representation of the physics of a pendulum, as well as bullets that didn't spark. His complaint with the Matrix wasn't about the physics within the Matrix, it was primarily about the humans-as-batteries nonsense.

      • His complaint with the Matrix wasn't about the physics within the Matrix, it was primarily about the humans-as-batteries nonsense.

        Usually I can ignore the scientifically implausible, but that even caught my attention when I watched the movie. I mean, it was just plain dumb.

  • Sniper Rifles (Score:5, Interesting)

    by lommer ( 566164 ) on Saturday June 15, 2002 @12:43AM (#3706485)
    I liked the comment about the sniper rifles and laser sights, mostly because they're wrong. They were correct in stating that the army doesn't use LASER sights for sniper rifles, however, as an army friend was recently telling me, they now use a form of IASER for sights.

    The IASER basically paints an infrared dot as opposed to a visible light dot, thus it can't be seen with human eyes. But, If one is looking through the infrared sight of a sniper rifle, it is clear as day. Thus, one gets all the advantages of a laser sight without letting the victim know of his impending death ahead of time.

    One thing to note though, is that these sights are only really practical on sniper rifles, as one would have to be wearing infrared goggles for them to work on normal guns.
    • So does the scope function as infared goggles then? How is this an improvement over crosshairs?
    • is that the beam travels in a straight line, the bullet does not. If the military is using them, then more power to them, but I'd bet they're only doing it at short range. Unless maybe they are the range finders? At any rate, for any appreciable range, you would have to tip the muzzle of the gun up so that the beam would completely miss the target. Unless, of course, they are adjusting the beam alignment in the field, but again this sounds far fetched.

      BlackGriffen
      • Yeah, and everyone says the Earth is ROUND, freakin' new wavers!

        Tell me another one! :-p

        hehehe
      • You've never sighted in a rifle have you. All light, including the light that enters your scope travels in a straight line. Bullets of course follow a parabolic tragectory, and since we know this you simply adjust you sight for the rise or more likely fall of the bullet at the expected range. If you are shooting at distances other than your sighted in range, you have to adjust your aim for the difference in drop.
        Scopes can be adjusted for ranges up to several hundered meters, so lasers should be equally good.

        • snipers (Score:2, Informative)

          by dhm4 ( 584969 )
          yep and (according to tom clancy) snipers use short impulses of laser to measure the distance to the target and can adjust their equipment exactly. for a good placed shot over a large distance they also measure the wind speed and air pressure and must be careful, that no vein is under their rifle arm.
          perhaps some soldier or weapon freak can help solving this problem...

          ---
          on /. nobody knows, that you're a god.

    • Re:Sniper Rifles (Score:5, Informative)

      by Eol1 ( 208982 ) on Saturday June 15, 2002 @02:05AM (#3706714) Homepage Journal
      No. Not at least for US spec ops.

      IASER is only used in regular infantry units from what I have seen and then only for night fighting. Prob is they show up bright as day in with PLAIN OLD NOD's. Has the same problem as tracers, they draw line back to the shooter. From what I have seen they are using these to replace tracers to solve the tracer visible line issue. Works great -v- 99% of our lowtec opponents though (who don't have NOD's). Sux just as bad as tracer -v- high tech opponents. Needless to say, this is A BAD THING(tm) if you an actual sniper where concealment is vital.

      Snipers I have spotted with all use good old plain scoped crosshair sites, though some like the dotted reflex sites. Key thing with both these is they ARE PASSIVE. This is a key requirement for snipers, you don't need to give you position away. Active snipers are reg. infantry sharpshooters...THEY ARE NOT ACTUAL SNIPERS. (Though they think they are). Giving a guy a rifle and a scope doesn't make you a sniper.

    • Re:Sniper Rifles (Score:4, Informative)

      by Ryan Amos ( 16972 ) on Saturday June 15, 2002 @01:17PM (#3708296)
      This is sort of right. Laser sights are pretty much only useful for close range fighting, where a soldier would need to "shoot from the hip" while maintaining some semblance of accuracy. Snipers often do use IR lasers, however, they don't use them as laser sights. That's what they have a scope for. The lasers are used as rangefinders, so the sniper can tell how far away his target is and adjust his scope accordingly.

      The problem with lasers is that they basically say "Look! Here I am!" And with infrared nightvision available for under $1000, it's not a stretch to assume the enemy has it as well. IR scopes are also not as common as you would assume. Their range is limited compared to a conventional scope, plus they're a lot heavier.

      One other thing to note is that extreme distance, a laser would be utterly useless for aim on a rifle anyway. Keep in mind the bullet travels on independent axes, both forward (inertia of the bullet) and DOWN (force of gravity.) At longer ranges, the bullet's path is going to look more like an arc than a straight line. Last I checked, lasers don't arc. This brings me back to the rangefinder. If your target is 1500m away (not inconcievable with say, a .50 cal rifle) the arc of the bullet is significant. You have to adjust your scope to compensate for the range (thus why you need to know how far away the target is.)

      Another use of IASER sights is to have special forces operatives "paint" targets with the laser for use in bomb targeting systems. This is much more effective than painting the target from the plane itself, as the forces on the ground can keep a better hold on the target and there's minimal risk to them, as they're not actually firing any rounds (and thus the enemy isn't looking for them.)

      So, essentially, the detriments of using a laser sight on a sniper rifle far outweigh the benefits. The main problem is that it compromises the snipers location (his best weapon) while not being very effective. Rangefinders are only in use for a fraction of a second, and aren't likely to be spotted. Lasers, even IR lasers, are stupid as sights at long range. The only ops who actually use laser sights do so at very close range (say, less than 20 feet.) At that range, your presence is already compromised, the bullets won't arc, and you can get a split-second faster target acquisition. But on sniper rifles they really have no point.

  • Feathers (Score:5, Funny)

    by Anonymous Coward on Saturday June 15, 2002 @12:43AM (#3706486)

    First, let us point out that the thirty-round magazine in a Mac 10 will be expended in a mere 1.8 seconds of sustained fire! If our shooter blazes away steadily for a total of only 3 minutes, his or her Mac 10 will spit out around 3000 chunks of lead at roughly 15 grams a piece. This amounts to 45 kilograms or a little less than 100 pounds of lead.

    That weighs almost as much as 100 pounds of feathers, right? Woohoo for physics!

  • Episode II, seismic missles in space? (Score:4, Interesting)

    by Fastball ( 91927 ) on Saturday June 15, 2002 @12:46AM (#3706492) Journal
    While I liked the sound effects of those seismic missles used in Episode II: Attack of the Clones in the asteroid belt, I immediately began to wonder if that would actually be possible since space is a vacuum. There's nothing for a seismic or concussive blast to move through, right? No air, water, or anything with mass.

    If you set off some sort of explosion outside the space shuttle for example, would the force of the explosion move through the shuttle?

    • That really pissed me off, it was such a tease. When I saw the explosion and heard no sound, I said to myself "OMG, this is like the first movie since 2001 (the space oddessy) to get this right." I was so excited; it really made me feel like I was in space. Then a second later, boom. *sigh*

      I don't know if maybe those were supposed to be electro-magnetic concussive waves or something, but whatever they were, it's impossible for sound to move in space. You wouldn't have heard them. On the other hand, as the site points out, flying debris moves through space quite well without any gravity or air resistance to bother with. I'd love to see a space movie where people were afraid to shoot at each other for fear of their own ships getting torn apart by the debris.

      People say that adding sound to the explosions and whatnot makes it more dramatic, but I totally disagree. The silent bits in 2001 were among the most nerve-wracking in any space film. I just don't understand why people insist on going "boom."
      • Well technically I'd think that you're vehical in space might constitute as a 'medium' for sound waves to travel through... and unless I'm mistaken we do use 'radio' astronomy to 'listen' to distant explosions in space (stars going supernova, etc.).

        Has anyone done a scientific test of listening to massive explosions in space, a supposed vacuum (not completely.. lots of dust) from an oxygen filled metal vehicle which might just possibly conduct sound waves to the human ear?

        That would be interesting.

        • Any sound would be from debris striking the hull and transferring the sound waves through the air inside. The addition of dust would not make a difference unless you have enough for it to constitute a medium (which because it is still a solid I suspect would be a lot). As to "listening" to supernova and the like I beleive this refers parts of the light spectrum we can't see (ie. radio waves), and as such we are still just looing at these phenomenon. In order to actually hear we would neeed some medium to transmit the physical shockwave to us which I don't really see as possible. As to 'hearing' the shock wave from the mine in the asteroid field the best explanation I can think of is some sort of very high energy plasma discharge, that would explain both the glowing blue ring spreading at a fairly slow speed and the sound would be generated with this mass of plasma struck anything and of course caused that to vibrate.
  • anyone old enough to remember the very short lived "auto-man" ??

    tron like 90' turns.....
    • Hey now! Automan totally ruled. I have a whole bunch of it in DiVX too! I remember liking it when I was a kid because it was the first show I ever saw that actually involved computers and, yes, hackers (the REAL kind).

      Granted, it's total BS, but it's entertaining.
  • The basic premise is flawed. Duh, thanks. We all knew that. It's even okay to complain about it. But when you go on about how the physics when trinity kicks someone in the chest are incorrect, well, you lose my respect entirely. The whole point of the Matrix is that you can bend some of the rules, but you're essentially imposing your will on 'reality', or in this case, the simulation. Those who know they are outside 'reality' are the ones who can do all this comic book shit. So basically, she visualizes kicking him and in her visualization he flies like a mofo.

    I lost all respect (and desire to view that site) when I read the matrix review.

  • This guys site goes into how red lasers can not be seen in the air.
    although I have not seen it, I have heard the new green lasers are visible in lower-light conditions in the air?
    anyone seen one?
    is this true?

    • Re:green lasers (Score:3, Informative)

      by Greyfox ( 87712 )
      My green laser is nice and visible in dark and low-light situations. That's because there's enough dust and crap in the air that it causes the beam to scatter. You're not seeing the beam, you're seeing minute particles reflect the beam.

      If you are a geek or have geeky friends the green laser's a must-buy. You have to be damn careful with it though; it's much easier to permanently blind someone with the green laser than a standard red one, and it's difficult to look directly at the spot it creates on a surface unless the batteries are almost flat.

      I'm still looking for a blue one :-)

  • Explosions in space (Score:5, Insightful)

    by SVDave ( 231875 ) on Saturday June 15, 2002 @12:57AM (#3706528)
    I am reminded of what J. Michael Straczynski, creator of Babylon 5, said about the sounds of explosions in space in B5. He said to think of it as music. In the real world, there's no music in the blackness of space, playing dramatically as ships go by, but even physicists don't get upset when they hear music in space in the movies. So think of the sounds of the explosions as music, added for effect.

    BTW, I was mildly amused by the ego on display in their review of The Matrix:

    The Matrix had real potential as a cerebral thriller. ... We would have preferred less oracle mumbo jumbo. ... The Matrix fails to meet its potential because it just can't leave the artificial science in the computer simulation along with the artificial intelligence.

    Somehow, I don't think the creators were aiming to make it a "cerebral thriller". If the maintainers of intuitor.com didn't like The Matrix, that's fine, but they should review the difference between "fails to meet its potential" and "fails to meet your expectations."

  • What timing (Score:3, Insightful)

    by DarkHelmet ( 120004 ) <.mark. .at. .seventhcycle.net.> on Saturday June 15, 2002 @12:58AM (#3706533) Homepage
    I come to slashdot to see this story after watching Crouching Tiger Hidden Dragon

    That would definately have to be physics from another universe...

    • Re:What timing (Score:4, Insightful)

      by mfago ( 514801 ) on Saturday June 15, 2002 @01:37AM (#3706640)
      "Crouching Tiger Hidden Dragon" was a Chinese fable.
      i.e. not meant to be taken literally.

      It is a great movie once you keep that fact in mind.

      • Exactly! (Score:3, Insightful)

        by edunbar93 ( 141167 )
        If I had moderator points, I'd mod you up.

        This is exactly what I say to people who have a problem with this movie. (and that's always the reason they have a problem with this movie, clearly they're not terribly imaginative.)

      • Re:What timing (Score:3, Interesting)

        by Lemmy Caution ( 8378 )
        Another way to put it is that some movies are fantastic by their very depiction and style, and that violations of physics - or psychology, or history - are acceptable and even expected parts of those genres. Crouching Tiger, Hidden Dragon is part of two well established traditions in film and literature: the Hong Kong action movie and the pre-industrial fantasy. Perhaps the problem with Hollywood bad physics is that Hollywood films otherwise make an appeal to realism - we'd object less (on a reflexive level) if that initial appeal to realism was never made.

    • Re:What timing (Score:3, Interesting)

      by NanoGator ( 522640 )
      "That would definately have to be physics from another universe..."

      In the beginning of the movie, I thought the stunts were just badly performed. In true MSTian fashion, I blurted out "Good thing their stunt doubles are trained in the ways of the force." Several people in front of me chuckled at that comment. Heh.

  • Did you see what write on "Falls" (Score:3, Insightful)

    by kinnunen ( 197981 ) on Saturday June 15, 2002 @01:03AM (#3706548)
    The general principle is that each additional meter of height is like adding the kinetic energy of another .45 cal bullet. Hence, a mere six-meter (19.8-foot) fall, which would be routine for an action hero, compares to being simultaneously shot by six .45 cal bullets, from a kinetic energy standpoint. True, bullets are incredibly lethal because they can easily penetrate into vital organs. A fall on sidewalk would lack the penetration. However, it's pretty hard to completely avoid injury from being shot six times with a .45, even when wearing a bulletproof vest.

    Now what kind of a dumbass analogy is that? You don't need to be shot by six bullets to get injured, one will do just fine. However I (and I'm sure most of you too) have survived 1-meter falls numerous times without injuries. Does that mean if I get shot by one bullet I wont get hurt? Hell no.

    Yes a six meter fall will most likely hurt you, but pick a better analogy.

    • Surviving a 1-meter jump is no problem for most people. A one meter fall, on the other hand, is high enough to cause injury more often than not. Try this: stand on your counter-top (about 1m high). Imagine yourself falling and not landing on your feet. Ouch. I've actually seen a woman fall 0m (she tripped over a curb) and break her wrist.

      That was the point of their bullet analogy. If you fall 1m and land on a spot on your body the size of a bullet--say, your elbow, it would be the equivalent of getting shot in the elbow. Of course, the force of the fall would have to somehow not be dissapated through your joints, muscles, etc...
    • Does that mean if I get shot by one bullet I wont get hurt?

      Nope. As the article mentioned, they are avoiding the effects of bullet penetration. If the energy of the bullet colliding with you was spread out across your whole body, like a fall does, then the two forces are equal. That's all he's saying.

  • This page is great! (Score:5, Funny)

    by Procrasturbator ( 585082 ) on Saturday June 15, 2002 @01:12AM (#3706569)
    Nitpicking makes a movie better! Every time I'm watching TV with my friends, and I see a physical error, I pause it with Tivo, and draw out a diagram of how it cannot happen. My friend threatened to shoot me with an Uzi for doing this, but I reminded him that a Mac 10 is what the REAL action heroes use.

  • Worst movie error (Score:4, Interesting)

    by Alsee ( 515537 ) on Saturday June 15, 2002 @01:13AM (#3706572) Homepage
    In my oppinion about the worst movie error was in "Voyage to the bottom of the sea".

    In this movie the Van Allen radiation belt above the earth catches fire, slowly roasting the planet. Pretty silly, but that's not the mistake I mean. In a rush to save the planet the nuclear sub Seaview races under the polar ice cap. The Icecap begins to break up from the intense heat and we get to see huge chunks of ice come crashing down on the sub...

    Think about that scene a moment. Submarine a hundred or so feet under water. Blocks of ice raining down and hitting the hull. What's wrong with this picture?

    +

    +

    +

    +

    ICE FLOATS!

    -
    • Obviously the gravitational fields were changed by the melting earth!
    • Blocks of ice (with a lot of mass) from high up on the glacier or iceberg or whatever break off due to heat and then fall due to gravity which gives those blocks enough momentum or inertia or whatever to continue travelling downward underwater for a while before the friction of the water absorbs enough of that energy for the displaced water to force the more buoyant ice back towards the surface.

  • Star Wars Death Star Physics (Score:4, Interesting)

    by vile7707 ( 470358 ) on Saturday June 15, 2002 @01:14AM (#3706575)
    Quoted directly from this page "Lawrence Krauss, in the book Beyond Star Trek, points out that an object with a quarter of the moon's mass, parked in geostationary orbit would create a tide producing gravity force 25 times higher than the one caused by the moon. This would flood coastal areas and disrupt geological formations resulting in earthquakes and volcanic eruptions, not to mention extreme weather changes.

    According to Krauss' calculations these disasters of biblical proportions would only be the beginning. If it took the mother RV an hour to slow down, the energy released by its engines would be about 10 times greater than the entire luminosity of the sun. We'd be fried before the aliens even arrived. In the movie, however, we are somehow miraculously spared from these inconveniences"

    So I guess the Death Star needs no giant laser cannon to destroy planets just grab a handicapped spot in front of any planet and watch it rip to shreds.

  • Not only physics... (Score:2, Interesting)

    by dargaud ( 518470 )
    Why limit this list to physics ?
    Movies can turn anything wrong for the sake of the (often bad) story. Climbing ? Look at Vertical Shitmit [imdb.com] or Cliffbanger [imdb.com] to convince yourself that not only the laws of gravity are being raped, but also common sense.
    Due to the amount of computer savvies around here, I won't even talk about computers in movies, which fortunately no longer have big spinning tapes since, ho, a good 5 years ago.
    And I'm sure lawyers laugh themselves senseless when they see one of those movie trials, as will do anything from fireman to house painter.
    "Don't let the facts get in the way of a good story" may be a good idea, but only if you have a good story in the first place. Anyone can suspend disbelief, but not if you have to turn your entire brains off, as happens way too often with Hollywood. The problem is that most people don't notice any problem with faster than light spaceships, people jumping down the 10 floor of a building or people being hit by 10 big calliber bullet and fighting on.

    Now about the page, they talk about exploding cars. I used to agree with what they say, gasoline being fairly safe and all, until two years ago. A moron on a cell phone ran into us while we were stopped in traffic. At about 140 km/h. Our car exploded in a big fireball instantly just like in the movies. I've been thinking about the physics of that ever since: the tank was full, it was very hot (about 40C), but still it was enough to give me a one year suntan. And we ran fast out of the fireball. Bah! enough!
  • Unless I'm mistaken, movies are not airplane simulators. Aside from documentaries or movies like "Saving Private Ryan", they are supposed be fictional. They will obviously add little effects like "bullet sparks" to add to the dynamic of the scene, even if they "violate the laws of physics". Really people, get a Life(tm)!
    • they are supposed be fictional.

      But fiction needs consistency and a connection to the real world to be successful. What if Captain Ahab had chased Moby Dick to land, wherein Moby and Ahab's ship sprouted legs and continuted chase? Would you have accepted that? Some of these physics errors are nearly that bad to anyone familiar with the subject, and come in movies that are set in realistic settings that shouldn't have whales sprouting legs and Macs interfacing with alien technology on an instant's notice.
      • My Mac connects to plenty of 'alien' tech on an instant's notice, (though I don't think instants can be possesive)... namely Windows, on a regular basis.

        I just thank the gods that it's impervious to alien viruses!

      • "What if Captain Ahab had chased Moby Dick to land, wherein Moby and Ahab's ship sprouted legs and continuted chase?"

        I would love to see that version, heh.

        What you said reminded me of Hithhiker's Guide to the Galaxy, particularly where the Improbability Drive turned a missile into a whale. How could a FTL drive do that? Because it was improbable! heh

        Just about any physics can be accepted in the proper context, which some movies fail to explain too well. Few people criticize animated movies, for example. However, the comment about the physics in the Matrix sparked a heated "It's all a computer simulation!" rebuttal.

        If you want an interesting example of context fixing scripting oddities, watch the first 3 eps of Robotech, and then read the first Robotech novel. (There are 6 books total....) There are some cheesy lines in the ep, but the book gave more attention to the context, while having the character deliver the exact same lines. I couldn't believe how much more mature it felt.

  • Science "Fiction" (Score:2, Insightful)

    by hibachi ( 162898 )
    I was really looking forward to reading this and expected to enjoy a good tongue in cheek look at Hollywood. What a disappointment. It read as though it was written by Rimmer following his mind patch on Red Dwarf. Uninspiring and anal retentive, derisive arrogance without just cause. As much as the author may think himself clever, perhaps he might care to compare his net worth to that of a big budget Hollywood producer and reconsider.

    Most sad I thought was the author confusing cinematic technique with scientific ignorance. The reason bullets spark when they hit something in a movie is so you know both that they didn't hit the star of the movie, and you have a sense for how close they came to hitting the star of the movie. Something the sound of ricochets alone does not convey. It's similar to the classic sound of cameras in film, like an old fasioned flash. Almost no cameras make that sound, it's just a technique that cues the audience. A trick so you know without thinking that the flash wasn't lightening, something wrong with the film, or simply something that won't distract people into thinking "what the hell was that?" when they should be paying attention to the story.

    Amazingly, he missed the most glaring sci fi physics invention - the tendency for space ships in film to bank like an airplane while making turns. Be that as it may, I'll take an X-Wing Fighter style high speed bank over a lumbering, time intensive, retro thruster burn as a "real" spaceship might be forced to make. Here's to invented physics!!

    Oh well, cool idea for a website, I am just disappointed with how it turned out. I would love to see more science fiction executed with pendantic formality, but I won't trade my flights of fancy away entirely for it.
    Cheers.

    • Re:Science "Fiction" (Score:3, Informative)

      by phillymjs ( 234426 )
      Uninspiring and anal retentive, derisive arrogance without just cause.

      I found the site to be entertaining in its derision. And I feel his pain, as a fairly intelligent geek whose intelligence is regularly insulted by the mass media which is dumbed-down for the great unwashed masses.

      As Homer lamented before he had Moe hammer the crayon back into his brain to make him a dope again, "I'm a Spalding Gray in a Rick Dees world!"

      Sadly, movies are not made for the intelligent minority, they are made for the people who need a "Caution! HOT!" warning on their coffee cups. The Matrix was probably the closest we'll ever get to a thinking man's movie, and I heard somewhere that even that was dumbed down a tad (IIRC, the enslaved humans were originally supposed to be part of a tremendously huge RAID via their unused brain capacity, instead of as an energy source).

      ~Philly

    • Re:Science "Fiction" (Score:3, Interesting)

      by NanoGator ( 522640 )
      "I'll take an X-Wing Fighter style high speed bank over a lumbering, time intensive, retro thruster burn as a "real" spaceship might be forced to make."

      Hey bud, I totally agree with your point about Rimmerian arrogance, but the geek side of me wanted to argue this spaceship banking bit...

      I'll use the Enterprise from STNG as an example. That ship (particularly the saucer section...) can generate a great deal of lateral thrust, presumably to hold a position close over a planet. It stands to reason that this thrust is much stronger than thrust from any other direction on the ship. I can imagine the ship banking to take advantage of the lateral thrust so that it can peform a 180 quicker.

      I'm not trying to deflate your point, I think you're right. I just have a hot-button with that particular issue because I don't see too many people actually thinking about how a ship like that might need to bank. Rather, they'd use a generic "There's no air in space, so an airplane could be pushed in any direction" rule of physics to say: "Ah, I found a flaw and can explain it, so I'm smarter than the people who don't care about the issue."

      Using a little more imagination, they could figure out a plausible solution. But there's no benfit to that. "Man, that just wouldn't work" sounds a hell of a lot cooler than my explanation for why it might work. (I could tell by the expression on my gf's face... heh)

  • He's complaining about the lack of realism in explosions...

    Distance from the explosion would reduce the number of projectiles striking a spaceship. However, impacting pieces would have the same kinetic energy they had right next to the blast. A spacecraft would have to use the time afforded by distance from the explosion to raise its shields or risk annihilation.

    Did NASA build something that I don't know about? :P
  • Whoops! We need to decompress the ship but we only have once space suit! I know, we'll give you this death shot and then revive you when we have pressure again. This from Farscape, no less.

    Only problem is being dead won't particularly protect you from the ravages of vacuum. Your fluids will still boil and make a mess of your innards. Bummer for John...

    As for the explosions in space, I'm going to rig my spaceship to add the explosion sound effect when something blows up. Just to piss them off :-)

  • I love this site because we geeks (especially those who are or are related to engineers and physicists) can't watch movies, especially action movies, without noticing the physics holes.

    Among my friends I say that Hollywood movie cars come equipped with a "C4 explosive chassis option" because they all seem to explode in a fashion more spectacular than Fourth of July fireworks at the slightest impact.

    The cars in Swordfish, however, must have come with the C4 chassis option and the mother of all low-rider "hopping" custom jobs. I saw one SUV in that movie hit another car, leap into the air, start a forward somersault, and then explode... in midair. Crazy Taxi has better physics when it comes to cars, than that movie.

  • Gee... (Score:2, Interesting)

    by UncleOlethros ( 581729 )
    And to think that all those movies were so realistic until they pointed out all the bad physics...

    I'm a physicst, and while I do appreciate the dangers of bad physics being masqueraded as real physics, I really don't think that's what's happening in movies. I don't know of anyone who was under the mistaken impression that the Force or Transporters or Jump Gates were real. I do get some odd physics questions from people sometimes, but their misconceptions don't come from movies, they come from lack of education.

  • This site is pointless, while some of what they say is true, some of it is just pointless nitpicking - clearly serving no further purpose than displaying how utterly smug its authors are. For example:
    The narrator stumbles into the realm of science farce when he says that prosperous nations sustain their prosperity to a large extent by creating the perfect low cost labor force: robots. According to the narrator, these robots require no resources beyond those used to create them.
    They then go into a boring lecture about thermodynamics and the impossibility of a perpectual motion machine. They didn't consider the possibility that when the movie referred to resources, it might have been talking about scarce resources, such as food. The robots could rely on any number of plentiful resources such as electricity or solar power.

    These are the people who give nerds a bad name.

  • Trinity (one of the hackers) jumps five feet off the ground and pauses in mid air before kicking a policeman just below his neck.

    I thought the pause was just that, a pause. Not just Trinity pausing in mid-air (uh hello, with that much time, the police officer could have ducked, shot her, emptied a can of mace.) Notice how no one else in the scene moves either. It's just a pause so we can see the cool sweeping camera effect as it circles around the scene. I believe it's called "Bullet-Time" or something.

    While the site is an interesting read, I think these guys are a little too eager to point out the flaws in movie physics. I don't know about the rest of you, but I don't go to the movies to see an accurate depiction of reality.

  • I'm probably posting this way too late for anyone to actually notice, and I'm probably being a pedant for pointing it out, but...

    From the article:

    A load of buckshot hitting a vest can be considered an inelastic collision. This qualifies it as one of the situations which can be analyzed using conservation of momentum.

    Momentum is always conserved. An inelastic collision implies that kinetic energy is conserved.

    High school physics is fun.

  • Asimov's Fantastic Voyage (and not just for Raquel Welch in a tight wetsuit).

    I think it was in Profiles of the Future that Arthur C. Clarke did a pretty good job of explaining why things, especially living things, are usually limited to being the size that they already are within an order of magnitude or so, but once you suspend that particular bit of disbelief Fantastic Voyage is a pretty good movie.

  • What about 2001? (Score:3, Insightful)

    by Ozan ( 176854 ) on Saturday June 15, 2002 @04:26AM (#3706990) Homepage
    I think including "2001 - A Space Odyssey" would have completed the review, stating that showing correct physics and making a good movie isn't impossible.
  • Best exchange I ever saw on a movie related messageboard some years ago:

    "Dude, the Crow 2 is so fake. The guy drives his motorcycle through a concrete highway barrier. No way at that speed on a two wheeled vehicle would he smash through that."

    Followup:

    "It's a movie about a GUY WHO DIED AND CAME BACK TO LIFE and you're worried about realism?"

  • How does they know these things are unphysical? (Score:5, Insightful)

    by rsidd ( 6328 ) on Saturday June 15, 2002 @06:25AM (#3707157)
    I'm not at all impressed by their movie reviews. Take AI, which gets their worst rating: they're not impressed that the robots are self-sustaining, "what about energy, refuelling, rebuilding?" They claim it violates the laws of thermodynamics. Well, first law -- how do they know it's being violated? Maybe the things run on solar energy, or geothermal energy, or some such thing which is not inexhaustible but is "forever" on the timescales we're concerned with. Second law -- the earth is not a closed system, it constantly gets energy from the sun. Second law doesn't apply. Maybe they have automatic robot factories which run on solar power, it's not impossible.

    That wasn't the only example. He can't conceive of a machine which can act as a helicopter and a submarine at the same time -- but a hundred years ago people couldn't have conceived of helicopters in the first place. Why should he evaluate everything by present-day technology?

    The Phantom Menace review was even worse. There was no real "physics" being objected to, only stuff like "if the force field can stop water, why doesn't it stop humans who are 80% water?" If we don't know how it works, how can we pass judgements on such things? Perhaps it actively detects the presence of humans or biological objects. Perhaps it only stops liquids and not solids. Perhaps any number of other explanations.

    Remember Clarke's third law: "Any sufficiently advanced technology is indistinguishable from magic." Conversely, in the movies, anything which looks like magic could be the product of sufficiently advanced technology.

    Overall, I'm not impressed.

  • Spiderman (Score:3, Insightful)

    by jaaron ( 551839 ) on Saturday June 15, 2002 @08:24AM (#3707312) Homepage
    I'm replying to this late and haven't read all of the posts yet, so don't kill me if this has been mentioned already.

    Did anyone notice that Spiderman's powers apparently allow him to fall faster than the pull of gravity? Every time Mary Jane is falling from the sky, he somehows accelerates and catches up to her. I don't care that he may be in a more aerodynamic diving form, there's no way he could catch her in such a short distance. It's little physics things like this that so many people miss. The general public's concept of actual physical principles is fairly poor.

  • My favourites in movie physics (Score:3, Insightful)

    by theolein ( 316044 ) on Saturday June 15, 2002 @08:29AM (#3707329) Journal
    1.People using other people as bullet shields. Unless it's a small gun or get's stopped by a particularly large piece of bone (the thickness of the actor's skull?) most jacketed bullets will go through the victim and into the guy behind him using him as a shield.
    2.Bullets being stopped by tables, car doors or trunks and wodden walls. A 9mm bullet will go through about 9 half inch thick tables and will quite easily penetrate a car door or trunk and hit the people in the car.
    3.The cars exploding on impact.
    4.Unlimited amunition(tm)
    5.The hero's ability to waste all the bad guys with his 9mm Pistol although they're firing at him with assault rifles on full auto.
    6.Sound in Space(tm) (brought to you by Microsoft DirectSpace(R))
    7.Fancy aerobatics in Space(tm)
    8.Drag in Space(tm)
    9.Aerodynamic spaceship that can't land on a planet (Alien got this right in the later movies)
    10.Amazingly humananoid aliens(tm)
    11.Slow, visible lasers.
    12.The abundance of artificial gravity in space ships.
  • Why, when two spacecraft meet in the middle of space are they always the same way up relative to each other? Surly with no gravity or reference points, it would not be unusual to meet other space craft in space that are upside down etc.

  • I don't mind most of it... (Score:3, Interesting)

    by SCHecklerX ( 229973 ) <greg@gksnetworks.com> on Saturday June 15, 2002 @09:00AM (#3707422) Homepage
    ...it is entertainment afterall, and movies are for escapism. We don't WANT perfect physics...BUT

    The one that really annoyed me was spidey's web being able to 'stick' to a steel bridge even with a friggin' car full of people hanging from it (and him). Please. Flinging the web around the girder would have been at least a 'little' believable.

  • Anime physics (Score:4, Funny)

    by Megane ( 129182 ) on Saturday June 15, 2002 @09:17AM (#3707481)
    And then there's anime [bright.net] physics [ajax.net].

    Like how you can jump on missiles in the air, and then they keep going in the same direction without deflection. All attacks must be called out by name, even if they're as simple as pushing a button on a control panel. The best pilots have hair that completely covers one eye. And of course, all the usual Hollywood ones like the guns that never run out of ammo (unless it's a plot point to run out of ammo), and the Stormtrooper Effect (best parodied by the Rambo scene in UHF.)

    Don't even get me started on the Laws of Anime Cooking.

  • My favorite part in the article... (Score:3, Funny)

    by sg3000 ( 87992 ) <(sg_public) (at) (mac.com)> on Saturday June 15, 2002 @10:49AM (#3707744)
    was when he pointed out how Itchy played Scratchy's rib like a xylophone, but when he struck a particular rib, it made distinctly two notes! That was some really screwed up physics!

    I heard someone got fired for that one.

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