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..."

Comments

Been there, done that.

[Anonymous Coward]

AKA. Mythbusters.

The "Hollywood special" from a few moths back.

Same topics all over again

[yohanes]

It seems that we have discussed this kind of things so many times. Hollywood are not meant to learn about real world. It is about entertainment.

Intuitor

[imaginaryelf]

I've always enjoyed intuitor dissect movie physics for some of the more popular movies.

http://www.intuitor.com/moviephysics/

Add one to that

[Mark Maughan]

You don't see people's skeleton glow when they are being electrocuted.

9 Bad Excuses for a Fluff Piece

[AKAImBatman]

First, let me preface this by saying that Hollywood is fiction. I think when we see the tanker truck blow up, the Power Rangers jump-kicking someone in the chest, or Neo fly through the air like Superman, we understand it's fiction. It's called "suspension of disbelief." It's what makes movies enjoyable. No one is really going to think that these things happen as regularly (or at all) in real life as they do in the movies.

That being said:

Explosions on the battlefield go boom right away, no matter how far away spectators are. Even a small thing, like the crack of a baseball player's bat, is simultaneous with ball contact, unlike at a real game.

In most instances that come to mind, the director takes care of this problem by zooming you in on the Volcano, shell explosion, or baseball hit. Once you hear the sound at the source, the director usually cuts away to the actors after the sound has arrived. (As can usually be surmised by the ash and dirt flying at the camera.)

Hollywood always gets this one wrong. On film, thunder doesn't follow lightning (as in real life, because sound is slower); they occur simultaneously.

To the human ear, they are effectively simultaneous if the lighting crack is close enough to the observer. Considering how LOUD the director usually chooses to make the thunder, I don't think it's that bad of a summation. How about we start worrying why the actors aren't taking shelter?

And because radioactive things emit light only when they run into phosphor - like the coating on the inner surface of a TV tube - you don't really need to worry.

This is actually incorrect. Radioactive "things" can emit light through two other methods:

1. They grow physically hot enough to glow red-hot or white-hot.

2. They heavily ionize the air around them, creating pretty streaks and rainbows.

However, the green-glow often seen in movies and cartoons does usually require the presence of phospher.

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.

Or... the kicker could be properly grounded. If the kicker is properly braced against the ground, it's not impossible to send an unbalanced opponent off his feet. The fact that you can pick an opponent up and toss him in a single motion demonstrates that. That's not to say that the exact situation of many fights isn't ridiculous (excuse me, rediculous), but the physics of the situation don't prevent a kicker from delivering a blow hard enough to knock someone off their feet. Perhaps even to the point of sending them flying. (Though it's unlikely that it would be to the point of many kung-fu movies on strings. There's only so much structural capacity in the human body. After that, you start breaking your own bones.)

Now when they miss their target and don't go flying across the room... :-P

But in the movies, buses and cars shouldn't be able to jump across gaps in bridges, even if they go heavy on the accelerator.

Unless, of course, there is some sort of incline for a takeoff (ever notice how the Duke boys always manage to find that conveniently placed incline?) or the second section is lower than the first, thus allowing for the jump to complete depsite the drop in altitude. (As the camera appeared to make the situation in Speed.)

The problem, though, is that their voices don't change. In reality, if you slow down motion by a factor of two, the frequency of all sounds should drop by an octave.

Smash cuts don't exist in real-life, either. Yet we don't complain about those. Slow motion is an entirely artistic thing, and is not related to the physics of the situation. At all.

Pretty much the rest of his arguments

Re:9 Bad Excuses for a Fluff Piece

[badasscat]

But the thing that was most ridiculous about this scene was that it was a bus. It's one thing when a Charger jumps a gap with a ramp. A bus, even going very fast, is going to have plenty of time where its front end is falling while the back end is still supported and even going up on the ramp. The result is going to be angular momentum imparted to the bus. So what should have happened is the front end of the bus dipped down faster than the center of mass, causing it to miss the lower section and end up landing upside down on the ground below.

Well, but you do realize they did actually jump a bus, right? This scene was not done through CGI or with a helicopter towing a bus over the gap. The bus really jumped through speed and momentum alone. The gap was not there - it was added later digitally (or rather, the freeway was erased) - but the bus did jump that distance.

Granted, it was a) a specially modified stunt bus on a ramp, and b) pretty much totally destroyed by the jump. But it's proof that you can jump a bus. It would not behave exactly as you describe. Keep in mind most buses are back-heavy, so with enough speed to keep the bus relatively level as it went over the ramp, the rear would actually drop as it moved through the air, not the front. With a short enough jump (as is all a bus is really capable of), the bus would probably come close to landing on all four wheels when all is said and done.

(Side-note - according to Wikipedia, they actually had to shoot the jump twice because on the first shot, the bus made the jump too smoothly, which supports what I'm saying above.)

Re:9 Bad Excuses for a Fluff Piece

[ceoyoyo]

Um... recall Galileo... the back of the bus being heavier will not cause it to fall any faster than the lighter front. Neglecting air resistance, but with something the mass of a bus that's not so bad an assumption.

You're right, they DID jump a bus. BUT, they had a special kicker on the end of the ramp that dropped after the front wheels went over. Watch the scene again... see how the front wheels seem to leap up? There's a documentary around somewhere showing how everything worked and the actual bus jump, but I can't remember where I saw it or what it was called.

Even a car will always land hard on its front wheels (if you're lucky) or its nose or roof (if you're not) after going off a static ramp.

perfect vacuum

[hobo sapiens]

How about the fact that there is no such thing as a perfect vacuum?

Hollywood movies suck so much it seems like they violate this one.

Number #1 broken rule

[Anonymous Coward]

Time is rarely shown as continuous, forward moving, and in real time.

They are always using edits, skipping stuff and even going backwards and forwards. Really makes it hard to enjoy a film with your sense of reality totally shattered.

Re:Some points aren't valid

[Rob the Bold]

If I punch a punching bag, the bag moves but I don't. That is because my fist has the energy which transfers to the bag. I don't go flying backwards as the article suggests.

Friction, dude. Try the experiment again on roller skates.

#4 and #5

[MeanderingMind]

I've got two complaints about #4.

1) The point of the Matrix was to bend the laws of physics. It was rather explicit.

2) The author obviously never watched Bruce Lee in action. If you plant yourself correctly you can send people flying across the room without moving an inch yourself. However, if you're in midair you certainly can't without the mentioned conversion of momentum.

Also concerning #5.

1) If it's a hole with level ends on both sides, it is entirely impossible to jump it on car without a ramp or other device to add a vertical component to velocity. However, in the event of a bridge being raised for a boat, the angle can potentially allow a vehicle to "jump" the gap. Is it likely or feasible? Not particularly, but it is possible.

2) This could have been expanded to include the "Bombs do not drop straight down" category of gravitational violation. A plane flying at high horizontal velocity v over a stationary target is not capable of dropping a bomb without horizontal velocity. Unless it fires the bomb backwards at a relative velocity -v, in which case we can have a semantic argument over whether the bomb is being dropped or fired.

Other laws

[91degrees]

Fast paced music doesn't really play when something exciting happens. Not everyone in real life looks like a hollywood actor. If people speak in a foreign language, you don't actually see an English language translation at the bottom of the screen. I tend to be pretty easy going on most non-realism since it is just there to tell a story. If the plot relies on a complete failure to grasp some basic fundamental of physics, (e.g. The Day After Tomorrow), I tend to be a lot more critical.

Re:Outerspace is Cold

[xtracto]

Something which is not really "physics" but I found interesting is about Suppressors:

1. They are called Sound Suppressors not "silencers". They do not "silence" the sound just diminish it.
2. They do not really suppress the sound the way movies put it (I am looking at you Mr. Bauer).

Motion pictures have produced the common misconception that sound suppressors ("silencers") completely silence the weapon's sound, or reduce it to a quiet whistling sound, which is in most cases very far from the truth. In fact, the emergent noise can still be heard from a fairly large distance. The quiet whistling sound associated with silencers is more attributable to the noise made by air guns 3. (And the most interesting for me) They are good just for a small number of shots (Yeah, again looking at you Mr. Bauer)

Very effective suppressors either involve a large total suppressor volume, a moderately large volume plus many baffles, or wipes. It is possible to design a very small and compact suppressor with wipes which effectively silences a pistol; these suppressors have a lifetime of as few as 4-5 shots and typically no more than a few magazines of ammunition. Larger wipeless (baffle only) pistol or rifle suppressors may be nearly as effective for long lifetimes (hundreds or thousands of shots) but are relatively bulky, clumsy, and heavy.

Wile E. Coyote

[kfstark]

I am a firm believer in the ability to break the law of gravity.

I was out surfing and paddled into a wave. When I jumped up to my feet, I missed the sweet spot of the wave and ended up on the breaking part instead (ie. not a good location). To this day I swear the wave dropped out from under me followed by the board while I hung there in midair. Misquoting Douglas Adams, "gravity finally looked my way and wondered what the hell I was doing" and down I went. The couple of people who saw it were sure I was surfing a board made by "Acme".

It was a really bizarre physical sensation I have not been able to adequately explain. (or recreate).

--Keith

Re:Wile E. Coyote

[inviolet]

I was out surfing and paddled into a wave. When I jumped up to my feet, I missed the sweet spot of the wave and ended up on the breaking part instead (ie. not a good location). To this day I swear the wave dropped out from under me followed by the board while I hung there in midair. Misquoting Douglas Adams, "gravity finally looked my way and wondered what the hell I was doing" and down I went. The couple of people who saw it were sure I was surfing a board made by "Acme".

That's possible: the water could pull the board downward faster than 9.8m/s/s due to surface tension. The board is somewhat 'stuck' to the surface of the water.

The same effect could explain how the water itself fell faster than 9.8m/s/s: wave action elsewhere created a suction below the water, such that atmospheric pressure above the water pressed down on it (and on the board), adding to the downward accelleration already provided by gravity.

the most famous example is not mentioned

[swschrad]

basically because the western has been out of favor for a long time.

I refer, of course, to the infamous 250-shot revolver.

basically, back in the black and white days, nobody EVER reloaded their guns.

you never saw any recoil, either, but that's because those movies were made when men were MEN and sheep ran scared, and those actors were truly made of steel, riding horses at a full gallop and able to hit a bad guy in the back of the head from 300 yards with a pistol with a four-inch barrel. and their arms never moved when the revolvers and rifles fired.

and the scenery along the trail repeated itself every 60 yards or so, but then we're not going for the top 2,000,327 movie lies here, are we?

Steel cases, not steel jackets, IIRC.

[Kadin2048]

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.

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 .223 Remington chamber, as opposed to the 5.56mm "NATO Chamber" or the compromise "Wylde Chamber").

Re:Outerspace is Cold

[Anonymous Coward]

yeah...or the fact I'm in MOTHERF*CKIN SPACE!

Re:Copper doesn't spark

[spun]

"the sparks generally are barely visible even under ideal lighting conditions"

Do they mean, uh, darkness? :)

Mood lighting. If you want sparks, you need mood lighting, a little vino, and some sexy R&B.