Artistic License – Physics
M.C. Escher certainly used this for his art.
"To some extent, it's understandable that space adventures play fast and loose with physics. After all, who wants to watch Han Solo spend years on the journey to Alderaan, only to find that the planet has twice Earth gravity and he can barely stand up, much less swagger?
Physics. It involves mathematics
and esoteric-looking equationsnote
to memorize, which is paradise to some but one level of hell for others
Writers often play fast and loose with physics - sometimes intentionally, sometimes not. This is usually acceptable when it makes for good storytelling and/or just plain awesomeness
, and one should always keep the MST3K Mantra
in mind. However, an egregious
violation of the laws of physics can result in loss of Willing Suspension of Disbelief
, especially in a story that tries to be taken seriously, or if the error could have been avoided with minimal revision.
When this is done properly, it can make for Crazy Awesome
action sequences and way-cool visuals - think The Dark Knight
, for example. Done badly, it can ruin the atmosphere entirely.
Some scientifically-minded individuals have a website devoted specifically to detailing these failings in movies: Insultingly Stupid Movie Physics
Soft Science Fiction
uses Artistic License
for physics extensively, as do many video games, war films, and horror movies.
with "How Is That Even Possible?
Sometimes people think this trope is applied when Reality Is Unrealistic
A Sister Trope
to Art Major Biology
, Cartoon Physics
(which fit Rule of Funny
more than Rule of Cool
open/close all folders
Anime & Manga
- One Piece
- In episode forty, a fishman believes that dragging Sanji to the bottom of the ocean will cause him to explode from the inside...this fishman clearly doesn't understand the way pressure works, or that there is the word "implosion."
- Admiral Aokiji, who can instantly, and probably completely to the bottom, freeze part of the ocean. Even waves that come crashing down on him are frozen in place.
- And Admiral Kizaru, whose Light powers frequently cause unexplainable explosions.
- One of the main elements of Humongous Mechas in Diebuster is called "Physical Canceller". It allows for such feats as making a Freeze Ray of negative million degrees - with character remarking that it should be impossible.
- Captain Tsubasa. That aspect of the series, specially of the anime, makes for a lot of running gags in the Spanish fandom. There's even an article trying to explain why the characters seem able to bend physical laws to their will. So far, they've reached the conclusion that Captain Tsubasa's Japan is a little asteroid orbiting the Sun, wich would explain why you can't see the goal until you reach the penalty area or how Tsubasa is able to jump twice the goal's height to score with his Scissors Kick, due to Asteroidal Japan's smaller gravity.
- The same applies to The Kickers, another soccer anime. Particularly a certain group of 3 people, whose trick shot includes jumping up, then doing multiple somersaults while staying in air for sometimes multiple anime minutes, somersaulting dozens of times in the process.
- The Tachikomas◊ in Ghost in the Shell: Stand Alone Complex are Spider Tanks that share the same size and weight of a small-sized car. They have wheels on their legs that can extend out into three-point toes for walking. Just standing up would present a balance issue if not for their AIs compensating that, but these same 4 small points of contact allow them to grip to a ceiling or a vertical plane such as a wall or the side of a building with very few problems. This is usually aided by the use of their synthetic thread-like wires, but they don't always need them to do so.
- On top of this, they're also capable of jumping from high places without leaving any form of impact wherever they land, and they can climb over a chainlink fence without bending it even a little. Nobody questions how a machine of it's size is capable of defying such common physics.
- My Bride Is a Mermaid pretty much runs entirely on a combo of Rule of Cool and Rule of Funny in regard to physics. For instance, in one episode, Nagasumi, in the form of a mindless giant, gets tricked into climbing on a space shuttle, which launches, carrying him to the moon in a matter of seconds. He gets back by getting hit by a magic lance that Sun throws all the way from earth. It's that kind of series.
- Hercules, of all people, feels the need to point out everything wrong about Ego compared to how planets are supposed to be structured.
- Ironically, Larry Gonick's Cartoon Guide to Physics averts this, despite using the Rule of Funny, all the actual Physics described in the book is accurate, if simplified in some cases.
- A 1950s comic by Jack Kirby has a Mad Scientist who hates humanity planning to fly into space to drop a bomb that would destroy Earth. He does so, but when he launches the bomb it doesn't fall as he expected, it merely floats where he dropped it off. Then he realizes he forgot there's no gravity in space!note The bomb explodes, destroying the spaceship and killing the scientist, but leaving Earth unharmed. Some scientist.
- A physicist is on trial for running a red light. He takes the stand in his own defense, and discusses the Doppler effect, eloquently explaining how the frequency of light one sees changes as one moves toward or away from a light source. Therefore, he argues that the red light appeared green to him.
- Unfortunately for him, his cross-examining prosecutor was a former student of his whom he had failed. The prosecutor asks, "How fast were you driving — a hundred thousand miles a second? Within a factor of two, perhaps?" After some explanatory exchanges about the parts omitted by the physicist, the judge dismisses the red-light running charge and convicts him of speeding.
- A more serious punchline would have the physicist prosecuted for two counts of perjury: claiming he saw the red light as green, and describing the light Doppler effect while omitting any indication of the necessary speed involved.
- The positions of the red and green lights on traffic lights are fixed, which is how color blind people know which one is burning.
- Although traffic lights can be vertical note or Horizontal note , the positions are always the same.
- Used as a plot point in the Polish sci-fi book Paradyzja. The eponymous Paradyzja is a xenophobic nation inhabiting a miracle of technology: a gigantic space station that rotates around its axis to generate gravity. Except not really. Paradyzja is actually just a bog-standard huge building located on a planet's surface. School students in Paradyzja are deliberately taught wrong physics so they don't notice the lack of a Coriolis effect, and visitors from outside are forbidden from bringing many harmless household objects that could be used to conduct a simple, telltale experiment.
- In The Simpsons, when Bart, Milhouse and Martin are reading about how Radioactive Man was formed Martin says in astonishment, "I'd have thought being caught in a nuclear explosion would have killed him!"
- "Well, now you know better."
- In King of the Hill, Hank and his friends try to tip Luanne's trailer home using only an unanchored winch (with no block) attached to a pickup truck. Of course, the truck, not the trailer, ends up being the one moved by the winch.
- Super Friends 1973/74 episodes
- "The Shamon U". Superman uses the vanes (sails) from a windmill to blow a space cloud away from Earth, despite the fact that there's no air in space for the vanes to work on.
- "The Weather Maker"
- The title villain uses a Weather Control Machine to somehow cause the water of a pool to freeze solid without the extreme weather conditions (such as a blizzard) that should be necessary to accomplish it. And to compound it, the water in the pool somehow completely thaws out a few seconds later, which should take hours to occur.
- An iceberg splits off a glacier and falls into the water, then sinks completely under the water and continues descending. This is impossible, about 10% of the iceberg should stay above the surface. Made worse by the fact that when an iceberg appears later, the narrator specifically says that icebergs can have up to 90% of their bulk below the water.
Note that this is not a trope so much as a series of things that may be goofs, may be a one-time use of artistic license for Rule of Cool, or may be a "proto-trope" in its larval stages, which will one day be common enough to be a trope of its own. As such, please list examples by "type" of physics violation, so we can catch these proto-tropes as they form.
Also note that this is not a forum. If an example is actually not a violation of physics, remove it. Don't debate it here.
Violation of Laws of Inertia and/or Momentum
Anime and Manga
- Spiral has a moment where Ayumu's sidekick tosses a key down to him from a moving train. Needless to say, it falls straight down in slow motion.
- In Hunter × Hunter, one arc has the protagonists and their allies playing dodgeball against an enemy. The game is won by one character making the ball stick to the enemy's wrists, while the enemy was trying to deflect the ball thrown by the protagonists back towards them, volleyball-style. According to the story, doing so made the antagonist be pushed back by the force of the ball until he was out of bounds, while deflecting the ball and changing the velocity of the ball to the opposite direction would have allowed him to hold his ground. The Law of Conservation of Momentum weeps.
- More or less every Shonen anime which features humongous energy beam attacks falls prey to this. These attacks typically display little or no momentum transfer, while also showing massively destructive effects otherwise. This generally ignores conservation of momentum. Even if the beams are assumed to be pure electromagnetic energy, photons still carry momentum. The recoil of even a city-smashing beam should suffice to throw the shooter around like a gnat in a typhoon, unless he's about as heavy as an aircraft carrier. And with the planet-destroying attacks shows like Dragon Ball regularly throw around...it gets much worse.
- Dragon Ball is however one of the few that did actually use the beams to create momentum in the shooter, albeit rarely.
- Also, it stands to reason that the shooter is always much more massive than he appears. After all, he has concentrated incredible amounts of energy inside his body, which serves as the power source for these beams, and logically must increase his mass, because energy also has inertia. Super Saiyan 3 Goku weighing as much as an aircraft carrier isn't all that outlandish when you factor in the incredible amount of energy confined in his body. Also, when fired from the surface, the recoil from these energy attacks tends to form huge craters.
- Applies to nearly every Mecha Show which lacks Inertial Dampening, especially those which feature Real Robots bouncing around like pinballs. Although it's possible that the phlebotinum du jour explains why the robot can move like that, most series fail to fully account for the effects of such violent acceleration on the pilot. Methods used to avert this include, in order of increasing effectiveness, (1) reinforced pilot suits and anti-motion-sickness drugs (Muv-Luv Alternative), (2) suspending the pilot in a gel or liquid medium (Neon Genesis Evangelion), (3) encasing the cockpit in some sort of Artificial Gravity field, possibly phlebotinum-powered (Super Dimension Fortress Macross and its sequels, although not explicitly stated).
Film - Live-Action
- The 1985 Squadron Supreme series featured a character named Inertia who's power was "stealing one person/object's inertia" and transferring it to another. This would be a cool and interesting power with many uses of its own but seeing this power in action, it's clear the character is actually transferring momentum or kinetic energy. Inertia is an object's ability to resist changes in motion.
- In the low-budget 1990 movie Captain America, the title hero is somehow able to redirect the course of a rocket he's strapped to by kicking it really hard. He kicks it so far off course that instead of the intended target, Washington, DC, he ends up in Alaska, somehow not exploding. And moving slowly enough for someone to take a clear picture of him from the ground.
- Some very bad simulations of microgravity were used on Bones, when Booth and Brennen interview an astronaut-in-training on board the "Vomit Comet". Not only did the microgravity-drifting actors push buttons and reach for objects without gripping the walls for stability, but when the plane leveled out and the characters settled back down, Booth's feet came down next to a pen and index card that were already lying on the floor.
- An episode of Doctor Who, "The Wedding of River Song", a train is seen driving into the Great Pyramid of Giza, here named "Area 52". Problem is that it's travelling too fast to stop safely within the pyramid - which it apparently does. note
- An episode of MythBusters shows a real world example of what happens when you try to violate this law: The build team builds a giant pressure cannon, and when they test fire the cannon, it nearly flies backwards off the table it's on. Grant points out they'd forgotten to take the mass of the hook they were shooting into account when they calculated how firmly they needed to anchor the cannon down; Kari flat out says "we forgot the Newton's Laws."
- The X-Files showed a falling elevator whose passenger was crushed to the floor - but two objects in freefall accelerate at the same rate (9.8 m/s2), so he would have felt weightless. In any case, the only way he could be crushed to the floor would be if the lift were accelerating upwards.
- Vector Thrust's Angle of Attack limiter is usually engaged to limit aircraft stress, but the player can toggle it on and off at well. When limiters are off aircraft start to behave like they're in space- you get things like planes flying backwards or sideways.
- The New Adventures of Superman episode "Rain of Iron". A villain on Earth fires an iron ball at an asteroid in space. The ball bounces off the asteroid and flies back to Earth. If an iron ball hit an asteroid it would just embed itself, not bounce away like a rubber ball.
- An episode of My Little Pony: Friendship Is Magic, "Sonic Rainboom", shows Rainbow Dash managing to break the sound barrier and create the titular rainboom, saving Rarity and the knocked-out Wonderbolts from falling to their deaths. However, she then does a 90-degree turn while still moving at about the speed of sound. A fan did the calculations and showed that Rainbow Dash (and the ponies she was carrying) would have experienced well over 1,600 times the force of gravity. On Earth, this would not only kill a living person instantly, it would probably liquefy his body. On Equestria, however, all ponies survive unharmed.
- Another fan did calculations based on a couple of other incidents, concluding that many things in Equestria, such as Applejack and random cloud-like swarms of butterflies, are actually composed of dark matter given the way they negate or transfer momentum.
- The cloud-like swarm of butterflies, however, is easily explained when you recall that Fluttershy is a pegasus pony. She can walk on actual clouds, which are a lot less dense.
- Any situation where say, a car is driving to the left, a man falls off the car and drifts to the right of the screen, then enters a stationary scene rolling toward the right which is the opposite direction they should be going. A result of the animator confusing relative change in motion between the man and the car, and the man and the floor.
- The first issue of Nemesis has the main character stand in front of the outside of an airplane...while it's in mid-flight. Before you ask, no, Nemesis doesn't have superpowers. Yes, the comic is supposed to be realistic.
- The Flash. While they address the issue of wind friction but giving him an immunity to the heat generated by it, he should have tremendous difficulty with acceleration (positive, or negative) at the speeds he travels. Obviously ignored because the story of a character limited to the speed of a drag racer wouldn't be as much fun.
- In an episode of Doctor Who, the Daleks are fought (in space!) with WWII front-engine prop planes, "modified" according to unspecified Dalek technological blueprints, that apparently still use the propellers for thrust, and which are able to perform complex maneuvers with no air.
- Despite a handwave mentioning gravity bubbles in the episode, implying that there was a field of air around the planes, it still does not explain away Newton's laws of motion. We still wind up with a closed system with the propellers just mixing up the air inside the bubble.
- The physics engines in Oblivion and Skyrim apparently don't support friction, which often leads to silliness when it interacts with dead bodies.
Anime and Manga
Film - Animated
- In the first arc of the X-Wing Series comics, an arc plagued with bad editing, a Wookiee swings◊ a wooden stick at a TIE fighter in flight and shreds the wing that he hit. He's not even knocked off balance and the stick is still intact and in his hand, but the TIE explodes. TIE fighters are a bit fragile for starfighters, but they're still space-capable fighters whose wings work as limited armor. And, in the books of the series, they're able to fly quickly through a forest snapping the branches of trees without taking on damage.
Film - Live-Action
- Up: Where Carl ties hundreds of balloons to his house to fly away. The problem is Carl's house's apparent loss of momentum. Realistically, it would be almost impossible to get going, and then would drag you a hundred feet when you try to stop. Also, the wind would move it better than you, so you'd just be dragged the way the wind blows. And air pressure is far enough from constant that the house wouldn't stay even like that. They also manage to steer the house with control surfaces that are tiny in comparison to the wind resistance of the house, and the balloons, and there's no apparent effect the direction the house is facing would have anyway, especially seeing as it should have no airspeed as it is unpowered.
- Stitch in Lilo & Stitch, who possesses super-strength, is able to pull a semi-truck to a stop. In the sequel, he actually keeps a space ship from taking off by grabbing onto it. In truth, regardless of how strong he is, a creature of Stitch's light weight could never do these things unless he also had super-anchoring powers.
- Stitch is dense, and therefore can't swim. He's the size of a small dog, and doesn't appear to weigh much more than one either; the five-year-old Lilo is able to lift him with minimal difficulty. Density is a function of both size and mass, so if he's able to pass for a dog in all respects, weight included, he should have the same approximate density as Lilo does.
- In Spider-Man, the Green Goblin cuts the cable of a cable car and grabs it to present Peter a Sadistic Choice. When an object hangs from a horizontal cable, it puts lateral force on the cable (to make it form a V shape, if that helps you visualize). A cable car weighs several thousand pounds. Even if we could Hand Wave the Green Goblin being able to carry that weight, it would have simply pulled him off the platform he was standing on.
- In Me, Myself, and Irene, Charlie's 'sons' manage to take off in a helicopter that, in reality, would have been unable to hover, let alone fly, with the weight of the three in question on board.
- In Escape from L.A. Snake Plisskin makes his final assault on the bad guys holed up in the former Disneyland via hang glider from Griffith Park. This is a straight-line distance of about 40 miles, which Snake manages to cover in only 10 or 15 minutes. Via hang glider.
- It's not like The Asylum is known for being on the deep end of the Moh's Hardness scale, but their 2014 film Asteroid vs Earth hinges on stupidity that may not even be quantifiable. Faced with an Earth destroying asteroid 1/4th the size and weight of the moon, one of the characters correctly informs the military that firing nukes at it won't work. He soon loses these Genre Savvy / Did his homework points by raising another plan, that requires that nukes be set off in and around the Ring of Fire in the Pacific. By doing so, he hopes to create a magnatude 18 earthquake that will move the planet out of the way of the asteroid. That would be 18 on the Ricter Scale. Pothole included for reference: every step up on the scale releases 31 times more energy. A little math shows that an earthquake of magnitude 18 would release a force equivalent to 12 zettatons (zettaton = 10 ^ 21 tons) of TNT. The crater from the asteroid that killed the dinosaurs only released 100 teratons (teraton = 10 ^ 12 tons). At this point, the plot is a non issue: no matter what is done, everybody on Earth is going to die.
- The novel Airborn has airships that use hydrium gas for their lifting power. This miraculous gas is specifically mentioned to be even lighter than hydrogen - an atom made up of a single proton. Let's see if we can figure out how many protons something lighter might have...
- An episode of G.I. Joe had the Joes get their aircraft carrier stuck in a derelict graveyard, and the only way to get out was to rig up a sail on it. Rule of Cool idea, but aircraft carriers are far heavier and more massive than wooden sailing ships and would need one heck of a sail or sails, a very strong mast connected to the superstructure of the carrier and a very strong wind to get moving.
- In one episode of Maya the Bee 3D series, insects are lifting a tree trunk with a lever by pushing the shorter arm. This would make necessary force bigger.
Radiation and Light Don't Work That Way
Film - Live-Action
- In the DCU Daxamites are vulnerable to lead radiation—for those not familiar with the periodic table, lead is generally considered a stable element in its most common isotopes, meaning it is not vulnerable to spontaneous radioactive decay in the same way that, say, uranium is. (This has been retconned into a severe allergy to lead, even in trace atmospheric amounts.)
- Plan 9 from Outer Space. Everyone should know that particles of sunlight are "made up of many atoms"!
- Eraser features the EM-1 portable 'railgun'. It is fitted with an 'X-ray scope' allowing the shooter to see the target through walls. Human targets are conveniently presented as skeletons with a pulsing heart clearly visible. First, anything we see is either reflected radiation (the the visible range of electromagnetic radiation) or radiation emitted by the observed object (like heat detected by thermovisual camera). X-Ray meant to pass through steel and concrete twice are unlikely to reflect of anything one may encounter in your normal surroundings (X-Ray machines are essentially slide projectors with human body acting as the slide). Furthermore, X-Ray capable of passing through concrete would also pass through bone with ease, plus the soft tissues, or the massive dose of radiation this would give out.
- In the Stargate SG-1 episode "Allegiance", someone invisible is running around causing trouble. Carter is asked to come up with a way to make him visible, and decides that the right way to do it is to get the naqahdah reactor to emit a burst of electromagnetic radiation with wavelength between 400 and 700 nanometers. While this may sound like Techno Babble, it actually means something — her plan is to make him visible by shining a light on him. Given how closely the numbers involved match up, it's unclear whether this is a goof or just a very subtle Expospeak Gag. Or both.
- In Sliders, after launching a nuclear rocket at a comet to destroy it before it hits Earth, Quinn is surprised when it doesn't explode on impact, however Arturo explains the delay is down to the limited speed of light. However, the light coming from the rocket approaching and hitting the comet should be delayed too, so it should still appear to explode on impact.
- 2nd Edition Paranoia states that red reflec armor blocks red lasers and nothing else, while blue reflec blocks all laser frequencies from red to blue. They explicitly lampshade this license, explaining that the game mechanics work this way because they don't want to deal with multiprismatic armor (like they did in 1st edition).
The Speed of Light is Faster Than That
- In a 1960s comic, the Flash once ran across a room and back faster than light could cross it once. While this itself isn't a big deal (any Flash can exceed the speed of light billions of times over without trying [which in itself is a bit wonky]), he did it while he was holding a conversation. Speed Force powers GO!
- In X-Men: First Class, before Banshee's first flight attempt, you have Dr. McCoy, allegedly a scientist, telling Banshee, "We need the sound waves to be supersonic!" Right, you need them to be faster than the speed sound... travels... at... huh? To be fair, he probably meant "ultrasonic" (i.e. above the range audible to humans).
- In The Wolverine, while fighting atop the bullet train, Wolverine charges at a mook many feet behind him by leaping up so that he remains in the same place while the train speeds by under him. In reality, Wolverine and the mooks are already moving at the same speed as the train, so jumping would at best provide only minimal deceleration through wind drag, as opposed to Wolverine temporarily flying like he's Superman.
- In The Lost Stars, humans have faster-than-light travel but not communication, and FTL travel doesn't work within a solar system—so in the many space battles, characters' information is limited by the speed of light. Usually this is done properly, but on a couple of occasions, characters on ship A see distant- ship B's reaction to event C (such as a fleet arriving from hyperspace) before A actually sees C (and they'll even have time to wonder what caused B to act as it did). Geometrically, that just can't happen—no matter where A, B, and C are, A will be able to see C before it can see B's reaction to C.
- The New Adventures of Superman. In several episodes the narrator said that Superman was traveling faster than the speed of light (186,000+ miles per second) within the Earth's atmosphere. That means in one second, he could fly around the entire circumference of the Earth (~25,000 miles) seven times! It then shows him moving for several seconds through the Earth's atmosphere.
- Mark Of The Ninja: During thunderstorms, you risk being seen by guards in a flash of lightning. However, to prevent the player from being caught by surprise, the thunderclap actually sounds before the lightning flash, not the other way around.
Wonder Twins Power! Energy in the Form of Heat!
Film - Live-Action
- In From Russia with Love, James Bond destroys a number of attacking speedboats over a large area simply by dumping fuel in the water and lighting it; however this would have no effect if the boats were moving at high speed, since they would be cooled by the splashing water (and its evaporation) faster than they could be heated; likewise, the bow-wave of the boats would extinguish the flames immediately around them. Later movies were worse. This could work if the area of burning fuel was large enough. Depletion of atmospheric oxygen by the combustion would cause the boats' engines to stall and the humans to suffocate, leaving them stuck in the middle...
- In The Wolverine, a superheated adamantium sword is depicted cutting through room temperature adamantium. While (in the canon) adamantium can only be made malleable by superheating it, superheating the sword would only render the sword more malleable, not what its cutting. Given X-Men Origins: Wolverine already demonstrated that adamantium can potentially damage other adamantium under the right conditions, the sharpness and angle of the sword strikes should have been sufficient to do the job, especially when backed by the strength of Powered Armor.
- Golden Sun. Kraden, attempting to cover for Camelot's bad writing, theorizes that things suddenly became very cold after lighting Jupiter lighthousenote , when lighting Mercury lighthousenote barely made an impact on the climate, because "wind cools more efficiently than water". This is exactly the opposite of how well wind cools things; air is a terrible conductor of heat. Air is indeed a terrible conductor of heat, but that doesn't mean that it cannot transfer heat efficiently. This is because wind transfers heat via convection rather than conduction, and convection is generally a far better method of heat transfer in virtually all applications. Changing the temperature of the oceans would certainly have a stronger long-term effect on global temperatures, but the effect of changing wind speed would be far more immediate.
Fire Needs Oxygen, Doesn't It?
Film - Live-Action
- Independence Day. In one scene, a traffic jam that fills a traffic tunnel in Los Angeles is incinerated at once, and the protagonists escape simply by ducking into a side door. Even if that somehow protected them from the blast, and from the temperatures of several hundred degrees that would have been generated, the fire would have taken all oxygen from the tunnel, and any survivors would have asphyxiated.
The novelization explains that there was a large floor vent in this room, and that it helped serve as an air intake when the fire blazed through, allowing the protagonists to continue breathing. Also the air stream would shield them from convection and cool them enough to counterbalance the radiation. Maybe.
- In Battlestar Galactica (Classic) episode "Fire In Space", there are areas in vacuum that are on fire. And everyone just tries to spray water instead of depressurizing the area, which would kill the fire in a matter of seconds.
This is partially justified for some parts of the fire, as there were personnel trapped in some areas with no lifesuits or escape routes. However, for areas like the Engineering, there's no excuse for not just evacuating and depressurizing.
- In Dead Space, one of the weapons is a flamethrower. It doesn't work in a vacuum, though its fuel is stated to be hydrazine, which is actually used in rocket engines in Real Life. This is corrected in the second game.
Large Objects Appearing In or Disappearing From Orbit
Film - Live-Action
- At the climax of the Doctor Who story "The End of Time", the entire planet Gallifrey appears next to Earth and apparently has no effect on either the Earth, the Moon, or their orbits. Gallifrey itself appears to already be moving the necessary orbital velocity, too, since it doesn't immediately start falling towards the Sun. This is somewhat justified in that Gallifrey was still phasing into our time from the Time War and wasn't physically there — but that's a whole 'nother issue.
- Smallville's grand finale had Clark shoving the planet Apokolips out of orbit. It was large enough to fill a large portion of the sky. Then there's the issue of how Clark suddenly had the power to both move a planet and counter the planet moving engines but that's another trope.
- Independence Day.
- The very presence of something as large as the mother ship in orbit should have caused flooding, earthquakes, and other severe problems with the Earth. And that's not getting into what the effects of it actually exploding in orbit would be. When it exploded, this would have been definitely been an "Extinction-Level Event" (to borrow the term from Deep Impact).
- Even earlier, when the alien mothership passes over the Apollo landing site, vibrations erase the astronauts' footprints. There's no medium for the vibrations to travel through. Also, it was supposed to be 1/4 the size of the Moon. Passing that close would have severely distorted the orbit of the Moon. Indeed the gravitational effects should have been detectable months before as distortions of the Moon's orbit around the Earth (which is continually being measured and can be done so with extreme accuracy). Plus the effect on the tides on Earth itself. And for that matter the reflected sunlight from the mothership should have made it detectable by telescopes long before it even crossed the orbit of Mars, and once it was in Earth orbit, it should have been visible to the naked eye and have been at least several times brighter than the full moon. The vibrations that erased the astronauts' footprints could have been due to "moonquakes" caused by the same gravitational stress that would have caused earthquakes on the Earth.
- However large the mothership is, it isn't solid. There's a lot of empty space in there, so volume-for-volume it's a lot less massive (and an object that appears a quarter the size of the Moon has only one-eighth the volume of the Moon; if "a quarter the size" means one fourth as big in every dimension," it's one sixty-fourth the volume). It's also shown as being fairly dark (the moon is about the color of asphalt, though, so that doesn't help much). That makes it worse, the Mothership was one quarter the Mass of the Moon and only 500 km wide, it should have been noticed weeks before it entered Earth orbit.
- Another Earth, Oh my, Another Earth. Admittedly this movie isn't about people running for their lives on the appearance of a twin of Earth appearing and coming in close to our planet - the movie is about grief and redemption with the second Earth representing hope. Still, that being said:
- The other Earth is always portrayed as "full" in the sky during the day (The way the Moon is full); it would have to stay on the night side of Earth to do that unless it was only being viewed at sunrise and sunset.
- A second Earth-size planet that near would would really throw off Earth's orbit. It would also impact other planets' orbits, though to a much lesser (but still detectable) extent.
- Even if the planet had been hiding behind the Sun the whole time before it appeared, we would have already been able to infer its existence from its effect on the other orbits in the inner solar system.
- If a planet were coming that close to Earth people would be more worried about a collision.
- Ocean tides here on Earth are the result of the moon pulling on the Earth. Another Earth so close as to be bigger than the moon in the sky would send ocean tides over huge swaths of populated land.
- And if it's that close, our own moon would have crashed into it.
- Based on the stated size of evil planet in The Fifth Element, at the orbital distance it is said to have parked by the time it was stopped a substantial part of it would have actually been within Earth's atmosphere. To say nothing of the tremendous tidal forces a body of its size would have exerted.
The Wedge Principle (no, not about underwear)
Films - Live-Action
- Superman's arch-enemy isn't Luthor or Brainiac, but the laws of physics. Due to the wedge principle, picking up anything substantially larger than himself would also trouble Superman, because he is exerting all force on one tight spot. The object would collapse under its own weight.
- The worse offender has to be Superman IV: The Quest for Peace, when he pushes the moon with little effort.
- Same in the movie Superman Returns, when he puts a Boeing gently down by holding its nose, and when he lifts a ship too.
- The physical complications listed above have caused some fans to speculate that Superman's power is not actually physical strength and invulnerability, but rather a form of telekinesis. For a while Post-Crisis, that was the canon explanation of his powers in the comics. It still is the explanation of the powers of Superman's blatant Marvel Universe Expy Gladiator.
- And again canon ever since Reign Of The Supermen. It was explicitly stated that Superman had a "field" around him that was difficult to recreate properly when they cloned him. That field is the source of his invulnerability, flight and super-strength, and he subconsciously wrapped it around anything he was trying to lift in one piece. Superboy was just able to use the field in a more complex manner. Eventually.
- This has actually been parodied in an old Donald Duck comic by Carl Barks, where Don granted superpowers tries to lift a sunken ship into the air, only for it to snap in half and slam into him from both sides.
- It was also parodied in an old comic strip by MAD's Sergio Aragonés in the Mad Super Special Fall 1981: The Comics. An ocean liner has run into a rock and is sending out SOS signals. Superman tries to rescue it by picking it up from underneath, in the middle of the ship's keel. When he does so, the ship breaks in half.
- And in MAD's "Teen Titanic" sketch, a version of Superboy with strength and fight and without TK tried to lift the titular ship out of the way of the iceberg (from the front, or bow). It promptly snaps in half.
- Aberrant actually points out and justifies this in-continuity. Regardless of how a power appears to work, it is actually a "quantum effect" which may incorporate various side effects to make it work like it should. This happens subconsciously, allowing Novas to make their powers work like they think they should work. A mentioned example is a Nova lifting a battleship, which should at most result in the ship breaking instead; the Nova subconsciously wraps the ship in a stabilising quantum effect so it can work "like it does in the comic books".
- Similar to the Superman example above, Tracy of Filmations Ghostbusters also has problems with physics. Example: In "The Curse of the Sleeping Dragon," a test of strength involves lifting a temple's pillar, thereby raising the roof. Tracy does this, but in real life it would cause the rest of the temple to collapse! In the episode, it doesn't.
- Super Friends 1973/74 episode "The Shamon U". Near the end Superman picks up a full size sperm whale from a city street and carries it back to the ocean. There's no way the whale could survive that much force being applied to such a small point on its body. It would have been ripped apart.
Relativity (it's not about Kissing Cousins)
Film - Live-Action
- Women Of The Prehistoric Planet, more well-known since being featured on Mystery Science Theater 3000, has a scene in which an alien spacefarer foots his mouth badly while trying to explain Relativity. He proclaims, "It's due to a warp in the time paradox." Nobody has to be a theoretical physicist to know that "time paradox" should have been "space-time continuum." Paradoxes have nothing to do with how fast time passes on an object traveling through space.
If it Burns Up in the Atmosphere, You're Fine
Films - Live-Action
- In Deep Impact, blowing up the second piece of the comet would not only not help, it would arguably make things much worse. If every piece still impacts the Earth (as in actually is stopped by the Earth or its atmosphere) you are still dumping all the kinetic energy of the comet chunk into the Earth's atmosphere! That's a huge amount of energy, dumped in practically all at once. It would still create a massive explosion, dwarfing all of our nuclear bombs combined. About equal to 10,000 times the global nuclear arsenal.
Bridge to Nowhere has Nothing on This
Films - Live-Action
- In I Robot the depiction of a damaged bridge crossing Lake Michigan shows a complete lack of understanding of how a suspension bridge actually works.
- This tends to be true for any film that shows a damaged or collapsed suspension bridge.note Generally, the central span collapses and the towers are pulled inward as if pulled down by it. However, a suspension bridge uses cables under constant tension to transfer the weight of the span to anchors or counterweights located at either end of the bridge, so the towers are normally kept in balance between the weight of the span pulling inward and the anchors pulling outward. If the span collapses, the towers would bend outward since the anchors would no longer be balanced by the span.
- The Dark Knight Rises has suspension bridges being cleanly severed in the middle, with the rest of the bridges remaining as they were.
- Godzilla (2014) shows that special effects artists still haven't figured out what really happens if you sever a suspension bridge's cables.
You Can Survive the Impact if you have Protection
Films - Live-Action
- In RoboCop 2, both RoboCop and RoboCop 2 fall over 100 stories — but survive undamaged and unharmed, due to the durability of their mechanical parts. While their parts may certainly have been that tough, their organic parts still would have felt the crunch of a very sudden stop inside those metal shells.
- Possibly justified by the third movie. Robocop's organic parts are apparently limited to Officer Alex Murphy's remaining brain matter inside an extremely sturdy casing that can survive impacts from bullets from automatic rifles and even the shrapnel and impact of near missed from ED-209's rockets, and his face (or a synthetic replica) attached to the front of said casing (this is lampshaded by a ganger claiming "cyborg EATS bullets," implying that someone may have had the bright idea of aiming for the mouth and finding this out firsthand). The brain is kept alive by artificial organs (such as a mechanical heart that needs replacing during the course of the film); this may explain why Robocop is unable to handle solid foods (his artificial digestive system may not be capable of processing something more demanding than baby food). Whereas Robocop 2 is blatantly justified at the time - the brain is kept inside a liquid filled jar inside a massive, heavily armored body that can shrug off anti-tank fire. And the brain inside was already sufficiently unhinged that any damage wouldn't have been obvious during the resumed rampage.
- Likewise, Indiana Jones in Indiana Jones and the Kingdom of the Crystal Skull can survive being hurled hundreds of feet because he's inside a refrigerator.
- Iron Man: Tony Stark survives a fall from hundreds of feet in his Mark I. Granted, some people have survived falls from that height but they typically didn't have a horizontal velocity to combine with the vertical from an arced blaster jump. He doesn't even seem to be injured. He later gets shot mid-flight by a tank and hits the ground without even a cracked rib.
- Oddly, it's averted in The Avengers, where a falling Tony is treated as though it will be fatal even in his armor. There Tony had just been exposed to a nuclear explosion, and none of the characters who were concerned had seen the earlier incident. Luckily, the Hulk was able to catch him and slow him down. In fact, he's specifically shown bleeding off the combined vertical momentum of himself and Tony.
- In Jules Verne's From the Earth to the Moon, the astronauts get to the moon by being shot out of a 900 foot long cannon. In order to reach sufficient speed to reach the Moon while traveling the length of the cannon, the ship would have to accelerate at 22,000 gravities, which would squash the astronauts inside it flat no matter what precautions were taken.
- Jules Verne, CS Lewis, and probably others committed this sin about spacecraft leaving the earth: the travelers felt their weight gradually decrease as they got further from the earth. Both the spacecraft and the travelers inside would be in free-fall (literally falling) and be effectively weightless.
- In Unreal Tournament 2004, you can partially negate damage taken from long falls by pointing your Shield Gun towards the ground and activating said shield.
Under Pressure (and not just the writers)
Anime and Manga
Films - Animated
- The second episode of Mobile Suit Gundam Wing has the Gundam Deathscythe fighting underwater with as much agility as if it were on land. The depths were far enough to be the giant robot equivalent of deep sea diving using specialized diving suits.
- Battle for Terra: In one scene, two humans are watching a room in which an alien is in an alien-atmosphere-pressurized room. Then a human is put into the alien's room, and one of the other humans has to decide whether he wants the human or the alien to live by changing the atmosphere or leaving it alone. He ends up choosing the human, but then, seeing the alien's breather mask, tells his robot to save her. The robot cuts open the glass, at which point the whole window explodes outward as the air in the pressure room escapes — even though this was after the atmosphere was adjusted to the same human-friendly levels it would be like outside the room.
- The phrase cubic pounds of air is used. Twice.
- The Dragonriders of Pern series: There's one part where suction cups are used to temporarily fix two objects together... in hard vacuum. Suction cups do not work in hard vacuum (since they rely on the pressure differential between the outside and inside of the cup).
- In one episode of Futurama, the ship is pulled underwater and manages to withstand the pressure all the way to the bottom (they're specifically stated to be at "the exact center of the Atlantic Ocean"). There's a bit of a lampshade hanging here, since when the Professor is asked how many atmospheres of pressure the ship can withstand, he says (with some sarcasm) "Well, it's a spaceship, so anywhere between zero and one." (Futurama loves to play fast and loose with physics in general, so this isn't the worst example of bad science even in this episode.)
Plate Tectonics is Not About Dinnerware
Films - Live-Action
- Twenty Twelve attempts to justify its scientifically predictable doomsday with an obscure geological theory of crustal displacement formulated in the 50s. The film even throws in an appeal to authority by claiming that Einstein agreed with the theory. The latter is true, and the film depicts at least vaguely accurately what crustal displacement in action might look like. What it fails to address though, is the fact that the theory was formulated before plate tectonics theory was developed, something that didn't happen until the 60s. What does this mean for the movie? Oh, only the fact that the two theories are mutually exclusive, and since plate tectonics is now proven true, the other can't be. Furthermore, Einstein, while brilliant, was not an expert on geology. You wouldn't trust his opinion on plate tectonics any more than you would trust him with open-heart surgery.
- In Mystery Science Theater 3000 The Movie, it's played for laughs when Mike releases the ravaged Hubble Telescope from being stuck on the Satellite of Love... and watches in horror as it suddenly drops out of orbit and burns up on the way down. He even points out that there's no way that should have happened.
Live Action Television
- In George R.R. Martin's A Song of Ice and Fire, the Wall is stated to be 700 feet high, yet people on the ground can fire arrows from wooden bows at defenders on top of the Wall and hit with enough force to kill. Not even modern compound bows could accomplish this feat. For reference, the average skyscraper is between 500 and 900 feet. This might be a good time to mention that the difficulty of accurately firing a bow 700 feet is nothing compared to the issue of not possibly having the strength to propel an arrow 700 feet UPWARDS (think back to elementary school science — one word, gravity). Though it is mentioned that, of the thousands of arrows fired at the Wall over the course of one battle, only one actually managed to hit anybody, and that guy only died because he fell off the edge.
- Most of the folks who spend time at the wall aren't even literate, never mind capable of trigonometry, and nobody has a 700ft. measuring tape lying around- given the state of disrepair the wall is in, it could be that it was 700 ft. tall once, isn't anymore, and people keep on repeating that number to each other so that way they feel safer from the ravening hordes below.
- It's said that, when George RR Martin saw a video game that faithfully recreated the size of Wall as described in the book, he admitted that he "made it too big". This would explain why the action around it behaves as though it were much smaller.
- In Iain M Banks' Consider Phlebas a crew are about to land on a ringworld, and the Captain tells them not to use their antigravity units: "Anti-gravity works against mass, not spin." Never mind what new physics they have to accommodate warpdrive and antigravity, acceleration by gravity and acceleration by movement are still functionally identical, and what works on one must work on the other.
- ... unless the technology was Exactly What It Says on the Tin. Literal "anti-gravity" would be a repulsive effect based on mass. If a person is standing on the interior surface of a ringworld, the majority of the ring's mass would be above him, resulting in anti-gravity technology having the exact (apparent) opposite of its usual effect, pushing him down against the ground. This sort of anti-gravity technology would, however, be useful for walking on the exterior surface of a ringworld.
- Averted in Robert A Heinlein's The Moon Is a Harsh Mistress. Soldiers brought from Earth to repress the rebellion on the Luna penal colony resent being there because it is nearly impossible for anyone to return to the Earth after more than a few months on the Moon because their body has acclimatised to 1/6 Earth gravity. The soldiers are also disadvantaged because their normal walking gait learned on Earth causes them to fly into the air. Also, a delegation sent from Luna to Earth must take long and very inconvenient acclimatisation measures just to not die when they arrive Earthside, and every step is an enormous strain. The older of them can barely even sit up without straining his heart, and he was born and raised on Earth.
- In Smallville, Commencement, meteors are said to take 45 minutes to pass the atmosphere when in real life this takes less than a minute.
- Rossini's opera William Tell climaxes with the title character standing at the bottom of a cliff, shooting an arrow upward that kills his foe (who was standing at the top of the cliff).
- Master of Orion II got "Graviton Beam" and Black Holes at once. It gives a weapon with a special effect and something to navigate around, but theories of gravity do not work this way.
Not Enough or Too Much Energy Shown
Anime and Manga
- Only every shonen fight, ever. Look at any big super powered fight from your favorite long running shonen anime (Bleach is a huge offender like Ichigo vs Aizen) and look how many times somebody uses an attack that could break mountains. There isn't a deafening sound, a bone breaking, or insane knockback from the attack. Also, there shouldn't be any light produced by an attack, no matter how strong it is, nor should the energy from the attack be rooted to where it actually should go (a body, an arm, the mountain, or simply the ground itself. Lastly, despite thousands upon thousands of cracks appearing from these moves, no deafening, ear-splitting earth-cracking is heard!
- Project Blue Earth SOS has a glaring example of not knowing their sciences. In the third episode, they launch an old fashioned space shuttle using oxygen and solid fuel. However, the observers are watching this craft take off from a few hundred meters away and are out in the open. Even ignoring the fact that the heat from the engine would likely fry everyone at that range, there is the rather large problem of sound. Space shuttle engines when taking off are loud, really really loud. They are loud enough to stop liquid from being able to flow - NASA discovered they when one of their electrical generators stopped working during takeoff. The sheer volume of the engine stopped the fuel from flowing. That level of noise would kill a human being for various reasons - including all their blood not being able to flow anymore.
- A Certain Magical Index:
- Mikoto Misaka's railgun is actually incapable of causing that kind of destruction. Actual lightning travels faster than 1030 m/s (the railgun's max speed). Assuming that this is so and using the weight of a 500 yen coin (~7 grams), the kinetic energy of each blast at maximum is at 3700 Joules, around the same amount as a .280 Remington fired at 861 m/s. But who cares about that when she's blasting someone off with her electricity?
- There is also angular kinetic energy (rotational energy) to consider, since a coin flicked at Mach speeds likely tends to spin like mad. But however much angular kinetic energy Misaka's railgun can realistically possesses, the destruction caused by it does still exceed any attainable limits.
- This may however have been simple lack of understanding of the amount of power needed to cause that damage on the part of the author. Given that she's supposed to be able to generate an output of 1,000,000,000 Volts, its entirely probable that the actual max speed of the railgun would be far, far greater than a mere 3 times the speed of sound. On top of that, the fact that all Espers are small scale reality warpers means that its entirely possible that her power bends, or outright ignores physics, changing them to whatever she desires them to be.
Film - Live-Action
- Revolution: Near the pilot's end, a DOS-based computer is used for communications (and, after all, it is in part a J. J. Abrams project). That is after an event that took out a big part of all electricity and other energy forms.
- Star Trek: Star Trek plays fast and loose with the amounts of power its weapons and technology require, sometimes greatly underestimating power output and sometimes greatly overestimating it-maybe. It's hard for us to know how much power FTL warp drives and cloaking technology would consume.
- Photon torpedoes are projectile weapons that rely on a matter/anti-matter reaction to cause damage. And yet for the most part they seem to act more like glowing cannonballs, mostly doing kinetic damage on impact. In reality, when matter and anti-matter come into contact they immediately turn into a great deal of light (most of that being gamma rays) and heat. So this◊ should look more like this◊.
- In the Star Trek: Voyager episode Riddles an alien outpost with 3,000 beings aboard is using 9 million terawatts. For comparison, all of human civilization used about 20 terawatts in the year 2008. That's 2,857 watts per human, 3 quadrillion watts per alien.
- In the Eraser movie mentioned above, the EM-1 'railgun' is said to propel the bullet (roughly the size of a .50 FMJ) to a speed close to the speed of light. As the kinetic energy equation [E=(mv^2)/2] shows, the muzzle energy of such weapons would be 1,8x10^18 J, i.e. close to 300 MT TNT equivalent (which is 6 times the yield of Tsar-Bomba, the most powerful nuclear device detonated ever). Even at half the speed of light we're still speaking about the yield greater than the one of the Little Boy. Also, due to relativistic effects, the mass of an object near the speed of light approaches infinity, so the energy would be too.
- Forget the the energy of the bullet: consider the power density of the battery required to pump out the juice needed to accelerate the bullet over a distance of just over a meter to "nearly the speed of light". Instead of the bad guys trying to sell weapons to some rinkydink rogue nutcase, they should be marketing the power supply to NASA, ESA, the Russians, the Chinese, or anyone else who want to toodle around in space.
- Deep Impact not only shrugs off the energy release by the asteroid hitting the atmosphere even if it's blown up into pieces, but it also greatly underestimates the power of tsunamis. A tsunami wave of that size would have completely leveled the city. There would have been no ruins left, only a flat wasteland.
- Forbidden Planet. The protagonists are fighting a monster, and one of them says that their attack has no effect even though they're hitting it with three billion electron volts' worth of energy. Three billion electron volts wouldn't fry a mosquito, much less a monster; no wonder their attack wasn't working!
- In Day of Sigma OVA, Sigma launches several large missiles, think ICBM sized, at Abel City. Several of these missiles touchdown and explode, leaving massive, smoking craters. Obviously, the shock waves from the explosions should've leveled the city outright.
- Cezanne tended to tilt the table and play with angles so that more would be visible.
- MC Escher was famous for his physics-defying artwork. The example image is a detail from his etching "Waterfall".
Live Action Tv
- One of the later levels in Devil May Cry 3 has a huge crush on the works of Escher.
- Torn World in Pokémon Platinum is based on Escher's works.
- A puzzle in God of War III involves using a trick of perspective to navigate an impossible Escher maze.
- Futurama Fry & Bender visit an Escher-esque apartment when they are house hunting. Fry comments that he's not sure he wants to pay for extra dimensions he's not going to use.
Fire Doesn't Work That Way
- El Goonish Shive: Somewhere A Physicist Is Crying. That would be Panel 3 of this strip. And he cries some more in this strip.
- Turns out this one is simple: A summoner wanted a fire monster, but there's no such thing as "living fire," so he ended up creating a monster that looks like fire but isn't actually hot and can be "extinguished."
- The comic's 'New Readers Guide' immediately warns us thusly: "WARNING: Often ignores the laws of physics." found here
Steam Does Not Puff That Way
...In other words, Steamflunk
Works of fiction that involve steam power sometimes overlook the basic way in which steam power actually works, or ignore the fine details so as to not bog down the storyline.
Specifically transgressions include:
- Steam engines are hungry. They use enormous quantities of fuel at a much less efficient rate than internal combustion engines, and have to be periodically refilled with water. Not only does this mean that operating a steam powered machine quite labor-intensive, the infrastructure needed to meet these demands is often overlooked.
- Between the combined weight of the engine, the aforementioned extravagant amounts of fuel, and the water required to make a boiler function, it is often stated that steam powered flying machines are a flat impossibility (there is no way to make a steam engine efficient enough to overcome all that extra weight). This is not actually true. Steam-powered aeroplanes have been made and flown.
- Steam power is dangerous. The steam pressure and boiler levels must be constantly monitored to keep the whole thing from exploding.
- Steam power is filthy, at least when the heat source is an actual fire and not phlebotinum. Anyone or anything in the vicinity of the machine is going to get dirty with soot and possibly coal dust. The machine in question will also have to be manually cleaned of ash and minerals built up inside of the boiler. Plus the staggering levels of smog and pollution in a steam-based society—the famous London Smog, for instance, came from so many residences and factories burning coal and venting the smoke right into the air.
- The reason steam is used in power plants is that it is very nearly the only way to convert heat into motion, and that motion to electricity is pretty damn efficient, upwards of 80%. This is also why wind and water power are so popular; they convert directly from motion to electricity. The conversion from coal to heat to steam, however, is something much less efficient, about 30% efficient. The reason steam power is used is because it works anywhere and on any fuel, not because inefficiency is a desirable thing.
- Disney's Atlantis The Lost Empire did a good job with this, at first. The submarine had several shots of a realistically designed boiler and engine room, and later, after the submarine was incapacitated and abandoned, the convoy of wheeled vehicles appears to include a giant tank of water. However, the film fails hard when "The Digger" rolls onto the scene. From the outset, this vehicle doesn't seem to have near enough boilers space (the moving parts alone are as big as a pickup!) When it briefly breaks down, it backfires flame—Audry then suggests fixing it with a part from a gasoline/diesel truck. Worst of all is when it starts making an idling sound like an internal combustion engine—seconds after Milo starts fiddling with the boiler.
- The spider, the wheelchair, and many other gadgets from the 1999 Wild Wild West film are stated to operate on steam, but do not appear to have any provisions for carrying and delivering fuel and water.
- The three fireplace-sized logs that Doc gives to Marty in Back to the Future III would not be sufficient to run a steam locomotive for a mile or more. This example overlaps with Just Train Wrong, because the idea behind a steam locomotive is to produce a steady, even source of heat and raise the water/steam temperature incrementally. Since there's such a large volume of fluid a significant, but short burst of heat probably wouldn't be sufficient to raise the pressure in any significant way.
- Not only that, but such a dramatic means of powering the train wasn't even necessary. The trains of the late-19th century were more than capable of achieving the speeds required by the DeLorean under the normal capabilities of their boilers.
Many, many, many stories (particularly SciFi ones) seem to completely forget that there is a huge difference between the support that water, air, and space (vacuum) give to a vessel. Things which are specifically constructed to work in one medium's density absolutely will not work in any other medium, unless specific consideration is given to constructing that item with both mediums in mind.
The primary offender is waterborne vessels being raised out of the water, and not immediately breaking apart. The buoyancy effect of water is very
substantial, and ships are specifically constructed to take advantage of that fact. Unless very extensive support is given to the vessel (i.e. practically the entire length and beam of the ship receiving physical support), the stress on the hull will immediately cause it to fracture apart in many places.
In other places, it's exemplified by "zeppelin-like" entities flying around, where the size of the buoyant airbag is ludicrously smaller than required for the size of the supporting gondola (or, more typically, full-sized ship hull) hung below.
While many fantasy and SciFi settings can handwave this problem away (due to Forcefields or the like providing sufficient support, or just plain magic), this is still a considerable problem.
- The (in)famous "baseball boat" of Pacific Rim - where one of the Humongous Mecha drags a long, skinny (but still massive) freighter along behind it, like a caveman would drag a club. And then proceeds to use that vessel like a baseball bat.
- The Mummy Returns with the zeppelin-boat thing, which is a classic case of not-enough-bag for too-much-ship problem.
Space is not an Ocean / Space is not like Flying in Atmosphere
Writers seem to ignore the fact that pretty much all "typical" effects behave differently in the vacuum and (mostly) non-existant gravity of space.
- With no atmosphere to provide lift, craft do not "swoop" or "fly" in any way resembling aircraft.
- Construction of spacecraft is radically different than for aircraft or ships, as stress from maneuvering can come from any direction, requiring radically different configurations. Designs that look like aircraft or ships absolutely will not work in space.
- Related to the Violating the Laws of Inertia above, writers completely ignore the fact that, in space, objects will continue moving in a straight line, at a fixed velocity, unless some outside force acts upon that object. This is a huge issue with correctly depicting space combat.
- Changes in direction require maneuvering thrusters pointing in several directions. A single fixed-direction main engine can not effectively change the craft's direction. Unless the writers are smart enough to show a ship gimballing in different directions before applying thrust. This requires showing the craft continue in a fixed direction, spin about on a central point (while still traveling in the original direction), then applying thrust to change direction.
- There is an exception to this in the form of reaction wheels, which are used to convert electricity into angular momentum. However, these can only be used to rotate a spacecraft, so maneuvering thrusters are still required for translation (moving sideways).
- As there is no friction (or atmospheric drag) in space, ballistic weaponry has no maximum effective range. Kinetic weapons (i.e. bullets) do not "arc" in their flight path. There is no "indirect fire" for ballistic weapons in space.
- For similar reasons, engines only need to fire when changing speed or direction, not fire continuously to maintain a fixed speed.
- There is no "up" or "down" in space. Vessels do not have to always be oriented in a single direction, and, in fact, there is considerable reason to NOT have them all oriented the same way, even if they're traveling in the same direction.
- For identical reasons, combat is much more 3-dimensional than even air combat. Rolling or spinning a ship while maintaining a fixed directional velocity is something that is a massive advantage in space combat.
- Maneuverability (i.e. ability to accelerate in different directions) is almost exclusively tied to thrust/mass ratios. For a variety of reasons (including having to carry around reaction mass in many cases), very small ships will be substantially less agile than medium-sized ones.
While technically not specifically under this (possible) subtrope, gross violations of the Inverse Square Law for energy intensity are common due to this effect, as the limited ranges common for water/air combat seldom cause the writers to think about how energy intensity is effected by the vastly different distances common in space. For example, it's easy to shoot a laser beam at an opponent a couple of miles away, and not presume too much loss of effect. Shooting the same beam at a spacecraft tens of thousands of miles away, on the other hand, will cause a potential "death beam" to feel like a penlight pointer when it hits the target.
- Science fiction films have long treated space flight (and combat) as virtually identical to WW2 carriers and ship/aircraft battles. Pick virtually any space opera or space fantasy story, and the spaceflight and space combat physics are completely wrong.
- The Star Fury of Babylon 5 is one of the very, very few instances where proper use of maneuvering thrust and gimballing is shown properly. Virtually everyone else shows it wrong. Including all the larger ships in that series.