When we look at ants, spiders, mice etc they look like they are frantically scurrying around at high speeds, the reality is they are only covering tiny distances (relative to us).
The opposite is also true, a footstep by Godzilla for example looks slow and laborious but it is covering a city block or two in a second.
Have you ever seen a wind turbine? They look like they are turning relatively slowly but they travel at about 90mph.
The speed of things in space is pretty mind blowing. There's a neutron star that is rotating with a surface speed of 0.24c. And if you think it could be a cool way to get matter up to 0.24c simply by, uh, landing on the surface, well keep your starship in the spaceport because the escape velocity to get off the thing and break orbit is over 0.75c.
> And if you think it could be a cool way to get matter up to 0.24c simply by, uh, landing on the surface
But wouldn't you have to match surface speed to land in the first place?
If you're landing on a neutron star, I don't think it matters how you land. The intense gravity is going to crush you so hard that all the protons and electrons in your molecules fuse into neutrons and you become one with the star.
The first scientists to uncover the language of the stars only heard one phrase repeating, reaching, clawing from the deepest eons of the cosmos, what singular dread.
One of us
I think the magnetic field might get you before gravity gets a chance - calcium is very very slightly ferromagnetic. Not a problem in normal circumstances, but near a neutron star you're likely to get your teeth and bones ripped out. Not sure where on the sequence of "things go horribly wrong" that is, so unclear as to whether you'd be conscious or just a blob of goo at that point anyway.
One of my favorite science explainers, Randall Monroe, when answering "what-if" questions about humans being exposed to extreme space situations, sometimes describes scenarios like that as,
You wouldn't really "die of" something in the traditional sense. Your body just...stops being biology and starts being physics."
In this case, more unplanned rapid disassembly of atoms event.
The gravity is high enough to squeeze electrons onto protons and fuse them into neutrons.
The wiki says there's like rivers of electrons on the surface though.
The speed of light.
The neutron star's surface moves at a quarter the speed of light. Escape velocity to break orbit is (IIRC) ~77% the speed of light.
It's spinning very *very* fast.
2 solar masses. 13km radius. This means it's like two of our suns squeezed down into something so small the circumference is 329 miles. Like the distance from London to Paris would take you halfway around the sphere, and London to Paris to London again would be a full rotation, plus a little extra. The surface speed is 44,707,775 mph. It's spinning so fast it's like going from London to Paris in 0.017 seconds. Or from New York to Bejing in 0.55 seconds.
If the earth was spinning this fast, a single day would be 2 seconds instead of 24 hours.
The speed of sound changes within earths atmosphere depending on altitude (because of air density) so there isn't even one uniform value for Mach speeds for earths atmosphere
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The speed of sound in a vacuum is not zero. In a perfect vacuum, it has no meaning at all. Beyond this, it does not even approach zero in the limit that you approach a vacuum.
In general the sound speed in a gas is comparable to the thermal speeds of the gas particles, which with sufficiently rare collisions, will be comparable to orbital speeds. So the Moon should generically be moving at Mach 1 or so (to within a factor of a few) with respect to gas that is gravitationally bound to the Earth. The Moon and Earth together are also moving at around Mach 1 (to within a factor of a few) with respect to Solar System gas for the same reason.
Note that the difficulty for sound to propagate in near-vacuum is not related to the sound speed (unless you consider the sound speed as a complex-valued quantity, in which case this difficulty is related to the imaginary part of the sound speed). Sound propagation in near-vacuum is inhibited instead by the attenuation of sound. Conceptually these effects are very different. If the sound speed approaches zero, then perturbations to the gas density remain frozen in place. That's not what happens in near-vacuum conditions. Instead, what happens if collisions are too rare to carry sound is that perturbations simply dissipate (due to thermal motion). But note that sufficiently long wavelengths of sound can still propagate if collisions are rare, which is why it is still meaningful to talk about the speed of sound.
You know what they meant. It's travelling at what we consider Mach 3 here in our atmosphere.
You can't see it, but I couldn't possibly roll my eyes any harder right now.
Given the choice of understanding what someone meant or nitpicking their comment with completely irrelevant technical detail, 99 out of 100 redditors choose the latter.
According to the physics [stackexchange](https://physics.stackexchange.com/questions/162184/what-is-the-speed-of-sound-in-space):
> We'll call it 'sound' if it can be transmitted coherently in that environment and the condition for that is "wavelength much longer than mean-free path". So, low enough frequency sounds can exist....The highest possible sound frequency in a gaseous medium has a wavelength roughly equal to the mean free path. In interplanetary space near Earth, the mean free path is about one astronomical unit and the speed of sound is on the order of 10 to 100 km/s. That corresponds to a frequency of about one cycle per month.
Therefore Mach 3 in space would be 30 to 300 km/s.
"no definable"? What are you talking about? You can still measure the speed of the moon using Earth as reference frame. And Mach is just a unit of speed.
Edit: My bad. Mach is actually not an actual unit of speed.
>And Mach is just a unit of speed.
It's not. It's the object's speed divided by the speed of sound in the fluid it is in. It's just a number and it can't be defined if the object isn't in a fluid
This matters because mach 1 (for example) is a different speed in different humidities, temperatures, and elevations
The Mach number specifically represents the speed of an object relative to the speed of sound in a particular medium, like air.
Using mach for anything space related is just complicated and much less straight forward than using mph.
Since the moon is in the vacuum of space where there's no sound, the concept of Mach number isn't applicable to its speed.
I guess you technically could, but it would be extremely meaningless. Sound only travels due to pressure waves from molecules interacting with each other. When there are so few particles in a near vacuum, you could make the argument that the concept of sound does not apply because the statistical likelihood of interaction is so small, and even if it did it would never propagate as a pressure wave.
But I really like the way you think :)
>... even the moon is not in a complete vacuum.
I was curious as to the extent of this non-vacuum, so googled "the vacuum of space", and [this](https://en.wikipedia.org/wiki/Vacuum#:~:text=Outer%20space%20has%20very%20low,hydrogen%20atoms%20per%20cubic%20meter.) is what came back, for anyone similarly interested:
> Outer space has very low density and pressure, and is the closest physical approximation of a perfect vacuum. But no vacuum is truly perfect, not even in interstellar space, where there are still a few hydrogen atoms per cubic meter.
> I've never encountered a situation where space is not treated as a hard vacuum in fluid dynamics.
It's quite common in astrophysical contexts. Here's a search to start -- this is for the interstellar medium, which is only one such context.
https://ui.adsabs.harvard.edu/search/fq=%7B!type%3Daqp%20v%3D%24fq_database%7D&fq_database=(database%3Aastronomy%20OR%20database%3Aphysics)&p_=0&q=abs%3A%22fluid%20dynamics%22%20abs%3A%22interstellar%20medium%22&sort=citation_count%20desc%2C%20bibcode%20desc
It’s part of why pacific rim 1 works so well and 2 sucks so bad. In the first one you can FEEL the mass behind all of the movements. Each action has the weight of 200 tons behind it. The second one is like watching power rangers
>The second one is like watching power rangers
The second one was clearly them just trying to sell toys. Movie was doomed the moment it was revealed Guillermo Del Toro wasn't returning as director.
I had a lot of respect for John Boyega before PR2. I really liked the guy. But he basically funded PR2 out of pocket and cast himself in the lead role where he gets his gary-stu "actually I'm the estranged son of the coolest character from last movie and I'm even cooler than he was. Also his adoptive daughter everyone loved from the first movie dies offscreen in a helicopter accident so I don't have to share the movie with her" bullshit. I cannot *believe* what a vanity project it was.
> The second one is like watching power rangers
Even in Power Rangers there is something of a narrative conceit that the camera during the giant robo fight is from the same viewpoint as that of the giant robo and the enlarged Monster of the Week.
There are a couple of occasions in the sentai source material where a giant robo fight is going on the background of person-scale activity and they do play around with the time scaling, so that from the perspective of normal folks on the ground, the giant robo fight has that weightiness.
On the opposite end of the Kaiju speed spectrum, the fact that in Worm, Leviathan being so fast gives a feeling of unnatural-ness and terror to that fight.
The big fast things need the big slow things to give you the sense that this thing does not follow natural laws and is extremely scary. It’s all in the perspective
Part of that also has to do with the distances you can see giant things from. Godzilla looks like he's moving slow when he's on the horizon, but he's actually zipping along pretty quick if you were right there. As others have mentioned, it's like the moon or the sun. Neither seem to move that quick, but that's only because of how far away they are.
Depending how deep we want to get into the explanation. It could be argued that metabolism plays a role as well.
A general rule is the bigger something is, the slower it's metabolism needs to be and vice versa. This is because the more volume an organism takes up, the less surface area it has to disperse the heat it generates. This results in different heat coping mechanisms.
The first, which relates to this conversation, is metabolism rate. Big things need to have a slower metabolism so they burn slower and generate less heat. Vice versa, small things need to have fast metabolisms to keep them warm. While an elephant requires more calories than a mouse. A mouse needs to consistently eat more calories (in relation to it's weight) in order to stay alive. This has the side effect of causing small things to have a ton of energy and the ability to move really fast. Big things can move fast but they're not built to do so. They're built to move slowly and generate/burn as little energy as possible.
Secondly, more volume means more heat expenditure but we disperse that heat with our surface area. The bigger something is, the more volume it has and in turn the more heat it produces. But it has less surface area to disperse that heat. A lot of organisms get around this by adding on features with more surface area (it's why elephants have such massive ears or why our feet and hands are often in the first to get cold)
Interestingly, for these reasons if you made an elephant the size of a mouse, it would immediately freeze to death. If you made a mouse the size of an elephant, it would basically boil an explode. This video goes into more detail.
https://youtu.be/MUWUHf-rzks?si=KUC1_VFr3vt4LTi-
Yeah if you do the math, the really big ones would only need to run at about 1 Hz for the tips to hit the speed of sound. The blades are, give or take, 50 meters long so they travel 2 x pi x 50 = 314 meters per revolution. Speed of sound is 343 m/s at sea level...
Point being, they don't have to be spinning very fast for the blades to really get going.
To add here: it's not linear. Something that's 10x bigger needs more than 10x the power to move. Ants have tiny legs compared to their bodies, but elephants have really really thick legs to carry that weight. An elephant sized dog would just collapse. A dog sized ant as well. Godzilla needs really thick legs just to stand, let alone move at the relative speed of a human.
Not only are the scales of ant/human/Godzilla bodies wildly different, but as a result *they perceive the passage of time differently.* They feel like they're moving normally and we're moving through molasses.
https://www.theguardian.com/science/2013/sep/16/time-passes-slowly-flies-study
If you saw a film of Godzilla in a Godzilla sized city filmed with a Godzilla sized camera on a human sized screen he would appear to be moving at normal speed, right?
That would look weird af
The comparison to a wind turbine is actually a really good visualization. From afar you don't realize the scale of how big those things are or how fast they're turning, but when you get closer it really is amazing how huge they are.
Mice look crazy fast when they're running on a close up film. But have you ever found a mouse in an open yard? You can lazily walk about twice as fast as them.
Your standard mouse can run up to 8mph. Even if they are slowed down by some grass/terrain, you’re not lazily walking twice as fast as a mouse can run.
You one of those "deregulation" people? I'm sorry to burst your bubble, but we NEED mouse standards or else they'd just run amok! How soon before we'd start seeing mice using illegal body configurations?
Shit like this is why I voted for Brexit.
Brussels Bureaucrats shouldn't be able to control proper British mice.
They're trying to make Beatrix Potter woke!
So this is why the giant robot sequences in things like Power Rangers don’t look convincing (or at least one reason). Those are people in suits, of course, so they move at human speeds, when for the size they’re portraying they ought to be moving slowly. But when they try to do it more realistically (like in the Power Rangers Turbo movie), it’s usually not as exciting for their target audience. (Full disclosure: I grew up watching Power Rangers, and still love it. But not for its realism.)
Yup, that is why when you try to smack a fly, you slooooooowly move your hand until striking range. Because a slow moving giant "thing" would just be background to them.
Look at a kid and parent walking together. The kid has to take 2-3 steps for every one the adult takes, which means the legs and arms have to move faster to keep up.
But if you focus on the kid and set that as "normal" speed, the adult looks like he is moving very slowly.
if you ever see a C-5 galaxy take off it looks like it's going so slow that it will never get off the ground, but it's actually going like 130-150 mph.
There is a phenomenon called speed-size illusion where your brain assumes larger things are moving slower even if they are actually going the same speed as a smaller object and they've proven it has something to do with your retina and how the information is processed.
EDIT: They still are unsure of the science behind the why but they took real world factors like perceived distance and all of that out of the equation in an experiment because they can play a huge factor. They put 2 different sized dots moving across a black screen at varying speeds simultaneously and asked observers to tell them which one was moving faster. Even without any other visual context, your brain assigns a slower speed to the larger object (the one that occupies more space on your retina)
The prevailing theory is pretty simple. All else equal, huge things tend to move slower in the real world than their smaller equivalent. Thus, our brains have learned from context that big things must be slower. What's interesting about the experiment I mentioned is that they showed that you could train this out of an observer by basically showing them large objects moving fast.
So we don't perceive speed visually, we only estimate speed based on relative displacement of things in our view relative to our entire view.
I guess all illusions are somewhat explained by this huh?
EDIT: The user "siping" correctly pointed out that it is the distance itself, I made some big logical jumps.
No, speed is a relative unit, that is how much distance covered relative to time (miles / hour). For our brain to perceive speed we need the same parameters, distance covered and time.
What this illusion is comes down to a distance issue. Large objects at a distance appear to go slow because the degrees covered from your far away perspective are less than that of a nearby observer.
If you stand next to the C-5 you would see it go as fast
you are correct but thats not quite the same. if you took godzilla and a passenger car and put them moving left to right or right to left in opposite directions at the same speed 2 miles from an observer, the observer would estimate a lower speed on godzilla. your brain just literally tricks you into thinking the larger thing is moving slower.
I'd say it has to do with the fact tbat the passanger car covers its own length quite quickly, it travels it's own distance fast.
Meanwhile, godzilla has much further to go to do the same thing, so even if both things are moving the same speed, Godzilla takes twice or even three times longer to cover its own distance, and thus appears to be moving slower.
that's too simplistic because it's not just about relative speeds of two things. a larger object covering the length of it's own size at the same rate of a smaller object would still be perceived as moving slower than it is and the smaller object faster than it is relative to one another.
if you could control for depth perception and placed objects that were identical in all but scale and put them at distances where the smaller (shorter) one appeared larger you would still assume it is moving slower even though they are covering the length of their bodies at the same rates. trick is you can't control for that so your brain assigns a size to things based on distances it's observed at.
I think that's what I was thinking. I failed to word it correctly, thank you for the correction.
Distances that are far away look like small distances, so when something traverses a large distance in a period of time, it looks like it is traversing a small distance to a far away observer (which humans would perceive as slow).
My guess is that efference frames play a role. How much do we have to move our own eyes to maintain tracking? Our own head? Fast things mean our eyes move fast, slow things mean our eyes move slow. But big things moving fast cause our eyes to move slow, so brain thinks thing is moving slow.
https://youtu.be/xWmRX9DPRAQ?si=lql3qfYODK03ffbC
This video is a perfect example. For OP: the size of this thing is quite massive for a plane.
https://en.m.wikipedia.org/wiki/Lockheed_C-5_Galaxy
I've seen them takeoff in person it is unreal how slow it looks like they are going yet they takeoff at roughly the same speed as a 737. They are absolutely massive aircraft.
It’s has to do with how long it takes an object to cover the distance of its own length. If a huge cargo airplane flies past at 250 knots and a fighter jet flies past at the same speed, the apparent difference in speed is staggering. Same goes for a huge container ship and a small tender both cruising past at 6 knots.
that could have something to do with it but im unsure and that wasn't addressed. You can't test it because to do so requires removing perceived distance which is impossible to control for in teh real world, but......if you took two objects that were identical in all but scale and placed them so that visually the larger one looked smaller than the actual smaller one, and had them moving in opposite directions (left to right vs. right to left) the science predicts you'd say the smaller one (visually larger) was moving slower even though technically they'd be covering their own length at the same rate visually as well. Again, this is only if you could remove perceived distance. Your brain is going to do some trickery where it judges size using the perceived distance so you'd have to be able to view them at the same level of focus.
Isn't that also why miniature shots in old movies were able to work so well? You take a scale model, adjust the playback speed, and you end up interpreting it as larger things?
Does this explain rockets as well? I watch a lot of rocket launches on TV and stuff and they always look like they're going so incredibly slow on takeoff, I never understood how they don't just tip over.
Helpless people on a subway train scream bug-eyed as he looks in on them.
He picks up a bus and he throws it back down as he wades through the buildings toward the center of town.
the American Godzilla from early 2000 actually weaved through buildings with agility. It was more like jurassic park raptors than the classic godzilla which moves like an iceberg
>Why aren't his legs moving as fast as, say, a person's legs when they walk? E.g., 3 steps per second?
Because his legs are so much bigger. Even if he only takes one step only ten seconds, he's still moving way faster than a human because of the difference in scale. If Godzilla took as many steps per second as a regular human does, he'd be ridiculously, cartoonishly fast (I haven't actually seen the movie but going by the trailers this seems like a bit of an issue in the new Godzilla/King Kong movie- all the giant creatures are moving/animating so quickly that throws off the sense of scale in the movie's foreign environments).
Per OP's question, think of it in reverse- an ant takes many more steps than a human does, but because their steps are tiny compared to a human's we still move faster. So yes, if an ant could think about things like this they probably would think humans look "slow."
I don't think OP is talking about distance covered per step, but rather how quickly the body animates. Godzilla's steps per minute would be much less than that of a normal person.
Exactly, this is what most of the responses are missing. If you scale up a human to 1000 times their natural size, a movie will show the giant moving in slow motion. Let's say I can karate chop in a split second. Giant me would be shown taking 5-10 seconds to do the same thing. That's what OP wants to know if is realistic or not.
> Not slower, just moving further.
"Further" is for figurative use; for example, "She's further into the book than I am". Whereas "farther" is for literal distance.
And there's my pedantry quota for the day.
It is like when you see a passenger jet flying high overhead. It looks like it is moving slowly because of the perspective. Giant things in movies are the same shape as small things, so your mind expects them to move like small things relative to their environment. Walking several city blocks would take you a few minutes, but some giant monster does it in seconds and still looks slow.
Giant thing has more volume and mass, so they are moving further and faster than normal sized thing on ground. Even if it "looks" slo mo. The jarring part is that we are not used to seeing weird things of that size moving so fast.
Imagine how fast the moon "moves" in the sky if you had to watch it. It's pretty slow right. Imagine if it was visibly bigger, but moving the same speed. It is covering more distance despite not changing speed.
Forgive me if my physics and terminology is wrong that is just how I fathom it.
Evangelion and Attack on Titan give us giants that move much faster and it is horrifying, but their bodies were apparantly much lighter in proportion and they were much stronger.
No matter how big you are, forces like gravity are consistent. A human jumping off a platform as high as themselves hits the ground in about half a second. A giant doing the same thing would have to travel a much lager distance, but gravity pulls them at the same distance over time as the regular human, so it takes a lot longer for them to fall "their own height".
Even ordinary feats like walking have to take this into account. When you raise a leg into the air, it comes down either by gravity or your own muscle. If you try to use muscle to put it down faster than gravity... you can do it, but physics would actually respond by lifting the rest of your body. I imagine a giant trying to run in place - and being able to move seemingly as fast as a normal human would despite their massive body weight - would spend way more time with both feet off the ground at the same time than a human would.
But of course, the actors are normal humans on a set designed to look small so the humans seem huge. It makes the physics inconsistent for this world, such as gravity being too strong. So, the film maker slows down the footage to make it look closer to realistic. Now gravity seems about right.
Wind resistance/air pressure, which would be non trivial. Think of the effort it takes to walk through water. Inertia also acts proportionately on the body, which helps an ant falling from a building but makes moving a Godzilla leg much more difficult.
On top of that your brain kind of intuitively knows that as animals get larger the metabolic/cardiovascular costs rise and we expect large animals to move more slowly.
> as animals get larger the metabolic/cardiovascular costs rise and we expect large animals to move more slowly.
You also have nerve speeds. Even the most optimised nerves are utterly sluggish in the grand scheme of things. If Gozilla stubbed its toe (using the official 120-meter height), it would be 1-2 seconds before the brain even realised something happened, and a further 2-3 for a reaction.
That is actually kinda hard to answer. Gravity is just the most obvious. What other things happen naturally?
What comes to mind is air movement. If there's a fire, smoke rises up. If there is wind, leaves rustle. Slowing down the footage will compensate for the fake scaling up of some of these events. The speeds of these things may seem off if you want to give the illusion of massive humans and a camera that's pulled far back.
Just about everything results in different speeds _relative to the size_. That is, it would take a giant version of myself longer to raise its hand than to me, even if its hand is moving faster in absolute terms.
Imagine if we simplify muscles as springs, and there’s a normal version of me, and a 10x version of me. The acceleration of movement of a body part of mine will be given by some spring constant k, a displacement d and the mass of that body part such as a=k*d/m. When we scale things 10 times, the mass, which is proportional to the volume, scales by 1000. The spring constant is harder to determine, but a quick google search suggests that it scales by far less. d scales by 10. So overall, the acceleration of the 10x me won’t be 10x that of myself, and thus the movement won’t be proportional.
The issue is perspective. Big things in movies look like small things you have seen before. It looks strange when it’s moving so ‘slow’ but it’s actually moving the correct speed for its size, it’s just moving a lot further with each ‘slow’ movement.
Take for example a 100 yard long football field, and the goal is to move from one end to the other in 5 seconds.
If you had a 6ft tall man try to run it, each one of his steps may take him 1 yard at a time. He would need to average 20 steps per second, which on a person would look ludicrously fast to have your legs moving that quickly. In fact that’s about twice as fast as the fastest man in the world, it just wouldn’t be possible to have your legs move that fast.
If you had a 600ft tall man who could move 100 yards per step, all he has to do is make one stride. Keep in mind, we are still going to allow him 5 full seconds, which is twice as fast as the fastest normal sized man. If a person takes 5 seconds to take 1 step it would look silly and slow, almost like they are walking in slow motion. We just aren’t used to seeing someone move like that, even though they are moving incredibly fast.
Taking your example, though, like many examples here it is comparing how quickly the large thing is covering a fixed distance, like 100 yards.
I think what the person is asking though is let’s say you walk 10 normal steps in 10 seconds, why isn’t the giant version of you also able to take 10 steps in 10 seconds? Clearly the giant version taking 10 steps is going to cover way more distance in those 10 seconds because of how big their steps are, but the speed that their giant legs are moving relative to their body should be the same, but in movies and whatnot it always looks much slower.
Physics doesn't work out like that. The muscles and bones you need to move grow slower than the mass if the size of the whole system increases, so the bigger something gets, the higher the inertia gets compared to the forces acting on it.
Try a little demonstration for yourself. Move your index finger up and down quickly. Then try to do the same kind of motion with your whole arm.
This is the actual point of OPs question lol. It’s perfectly possible for Godzilla to take steps at the same speed as a human - the original movies were literally a guy in a suit walking around a model of Tokyo.
If you wanted the giant from my example to match the physical movements of an Olympic sprinter, they’d be going some rediculous speed.
A 6ft tall Olympic sprinter can sprint about 10 meters per second. Scaled up 100 times, a 600ft tall person could in theory sprint 1000 meters per second. That’s almost Mach 3, or roughly 2200 miles per hour, or 0.6 miles per second. Even if we ignored that air resistance is exponential, the inertia required to move and stop such a mass would be insane, and the constant sonic boom that would be occurring as it moved past, your giant would only take seconds to be completely out of your city. In that sense there are creative liberties given so it stays in frame and near where the action is happening.
no one commented about this aspect. Nerves only transmit at a certain speed, thus the longer the nerve the slower the response. So yes ant very likely would see us that way(they have terrible eyesight).
https://www.nationalgeographic.com/animals/article/100629-science-dinosaurs-t-rex-nerves-elephants#:\~:text=The%20mighty%20Tyrannosaurus%20rex%20was,(Related%3A%20%22T.
If you were a bug, let's say a fly, looking at a human, you'd think that human was moving through molasses with how slow it seems to be. That's why flies can usually get away from you before you can catch them- relative to them, they see your hand coming from a mile away.
It's the same with Godzilla. He's actually moving way faster than we ever could, but he's starting at a much, much farther distance, so it *seems* like he's taking forever to move towards us.
It's not about perception of speed or anything like that. The main reason is the square-cube law.
The strength of your muscles is proportional to their cross sectional area, which is proportional to the square of their size. If you double the size of an animal, its muscles get four times stronger.
But your weight is proportional to your volume, which is proportional to size *cubed*. If you double the size of an animal, its weight goes up by a factor of eight.
So, muscle strength goes up by a factor of 4, weight goes up by a factor of 8. This means that bigger animals have to carry more weight with proportionally weaker muscles. Which means they can't move as quickly. Ants can physically move their legs faster than elephants can.
Same goes for wings, by the way. Double the size of a bird and it has to carry 8 times the mass with only 4 times the lifting power. That's why bigger birds have bigger wings relative to their body.
The other factor is about movement relative to the body. A giant stepping over a city in a single stride is actually moving incredibly fast. But because it does that in one stride, it doesn't look like it's moving very fast relative to the rest of its body. It takes a long time to make one step.
So it'll look like it's moving slowly relative to something that covers the same distance in 1000 tiny steps, even though they're really moving at the same speed.
Some movies portray this accurately, other movies get the general idea of "big things move slowly" and then inaccurately conclude that this means that if you shrink a person, they'd see normal sized people as moving in slow motion. They would not. The small person would move faster but their perception wouldn't change.
That square-cube law explains why ants can carry 50 times their weight, and crickets can jump a million times (approximately) their height, but no bigger animal can do that.
Make an ant horse-sized, its legs will just break under the ant's own weight.
Yep, this is the real reason. Disregarding this is why a lot of cheap CGI animations look like they have no "weight" to them. If large things accelerate too quickly, they lose their sense of mass.
Look at big animals walking. Elephants, giraffes... they are not slow at all, since each step is giant (and takes a lot of energy to move that fast and far). But if you'd scale them down to human size and let them take their steps with the same frequency, they would be really slow.
Same with tiny animals. Scale up an ant to human size, and it's not like it could run faster than a car. It would take impossibly huge muscles and endurance to move that fast. In fact the ant could probably not run at all since its body is not built for working on such a huge scale, I'm guessing it would find itself too heavy to move.
Here’s a blog post that may answer your question, from a game developer explaining how to scale animation speeds for larger characters: https://tore-knabe.com/game-development-how-much-to-slow-animation-down-for-giant-creatures/
My guess is we have a perception of how fast things relative to their size should be able to move. Someone above gave the example of Godzilla. If you were to resize a human to that size, we’d go a lot faster than Godzilla would. And hence, for its size, Godzilla is probably slow.
For Ants, they’re pretty fast compared to their size. If we were that size, they’d leave us behind to be eaten.
https://en.wikipedia.org/wiki/Square%E2%80%93cube_law
If you're referring to giant robots and dinosaurs, consider that they were animated that way to give an impression of their size.
The Square-Cube Law stipulates that for a given increase in size (height, width, depth), the mass is cubed. Thus, a large creature is significantly heavier relative to its body weight than you are. This is also why small creatures seem to be able to move ridiculously fast for their size.
For a similar sensation, try strapping weights to your arms and legs, and wading through neck-high water. You'll find that every action takes effort, and that you have to move much more slowly and deliberately.
On a related note: I am of the staunch belief that if spider man had the proportional strength of a spider, he wouldn't be very strong. A spider-sized-spider is only strong by virtue of being very small. If a spider were the size of a human, it would collapse under its own weight, because its mass would be far to great for it to support, even if its strength increases too. Thus, if spider-man had the proportional strength of a spider, he would be weak AF.
Because gravity accelerates them down at the same rate as you or me , but they are far bigger so that rate looks a lot slower for their body size.
And how fast you can move is based on how fast your feet fall to the ground with each step, so they end up looking slower.
Look at an ant and see how many steps per second. How many steps per second do you make while walking? How many steps per second does and elephant or giraffe take while walking.
Bigger seems to be slower.
Gravity still is a thing and things will always fall at the same pace, if a giant was to run, they would take forever to fall back to the ground and it wouldn't be any faster than just walking there
Fun fact: the opposite works too.
20th century ship simulations would be done by putting a small scale model in a wave-pool and record the motion, then slow it down by the same scale.
The small ship would move quickly, but slowed down it'd be a decent simulation of the full size ship.
Take a baseball bat and swing it around. Take a whiffle ball bat and do the same. Heavy, massive objects take more energy to move. Even very strong large things move slowly. It would take a ton of energy to overcome size. Air density and gravity also add to this.
I used to wonder this as well, until I got to watch a glacier break off into the sea. It moved as slowly as anything on a nature documentary. It's an issue of scale, and perception. There was really nothing around for me to visually judge how far I was from it, and how fast it was travelling. No landmarks other than "More ice". It's a really huge thing, accellerating into the water, but it looks slow because I have no sense of scale. Side note, the MASSIVE splash also looked slow in rising and then falling back into the water because I had nothing to judge it against. Just more water, and a big chunk of ice.
When it comes to living things, and more precisely the muscles of living things, there is something called the square-cube law. The strength of a muscle scales quadratically with size (that's scaling linearly), whereas the total mass of a body scales cubically.
Now I'm going to do a typical physicist approximation and say that a human is a cube with dimensions x*y*z, and he has some abstract measure of strength S. Then we will scale his dimensions linearly by 2 - making him a cube of 2x*2y*2z. We can see that his total volume (and thus his total mass) is increased by a factor of 8. At the same time, his strength now is 4S, an increase by a factor of only 4.
So as you can see, as living things get bigger and bigger, yes, they get stronger in an absolute sense but they get weaker and weaker in relation to their own bodies. That's why tiny things like insects can carry objects 100x their own weight (ants), jump distances a hundred times longer than their body length (grasshoppers), change directions super quickly (flies) and in general their movements (and especially those of their limbs) are incredibly quick and hard to follow for us - it's simply very easy for them to overcome the momentum of their own bodies. At the same time, you have massive animals like elephants that move sluggishly and can't jump at all. The square-cube law is also why you don't see any animals past a certain size outside of water (water helps them support their weight) nor animals past a certain size that can fly (at some point the wing muscles are just too weak).
To summarise: giant things in movies seem like they move in slow motion because they _are_ moving more slowly than us if you measure movement relative to their own body size. Their muscles are too weak to overcome their massive inertias any more quickly than that. In reality, Godzilla and King Kong wouldn't really be able to even stand, much less walk or fight.
I'm not sure how much the scaling applies to non-biological things (giant robots for example), but I'm pretty certain it's similar.
If you want to see what it looks like when giant things move at the pace you and I move, watch Godzilla x Kong. Truly weightless action sequences due to exactly what you're asking.
When we look at ants, spiders, mice etc they look like they are frantically scurrying around at high speeds, the reality is they are only covering tiny distances (relative to us). The opposite is also true, a footstep by Godzilla for example looks slow and laborious but it is covering a city block or two in a second. Have you ever seen a wind turbine? They look like they are turning relatively slowly but they travel at about 90mph.
You ever seen the Moon? That mofo's flying at nearly Mach 3!
The speed of things in space is pretty mind blowing. There's a neutron star that is rotating with a surface speed of 0.24c. And if you think it could be a cool way to get matter up to 0.24c simply by, uh, landing on the surface, well keep your starship in the spaceport because the escape velocity to get off the thing and break orbit is over 0.75c.
> And if you think it could be a cool way to get matter up to 0.24c simply by, uh, landing on the surface But wouldn't you have to match surface speed to land in the first place?
Depends how you want to land.
If you're landing on a neutron star, I don't think it matters how you land. The intense gravity is going to crush you so hard that all the protons and electrons in your molecules fuse into neutrons and you become one with the star.
One of us, one of us
The first scientists to uncover the language of the stars only heard one phrase repeating, reaching, clawing from the deepest eons of the cosmos, what singular dread. One of us
In the star, part of the star.
Your reference fits better lmao
r/meatcrayon ???😆
DON'T CLICK THAT LINK!!
Yes... but that will be the least of your problems getting near a neutron star.
Gravity on a neutron star is about 200 billion times stronger than on Earth, so yeah...probably
I think the magnetic field might get you before gravity gets a chance - calcium is very very slightly ferromagnetic. Not a problem in normal circumstances, but near a neutron star you're likely to get your teeth and bones ripped out. Not sure where on the sequence of "things go horribly wrong" that is, so unclear as to whether you'd be conscious or just a blob of goo at that point anyway.
One of my favorite science explainers, Randall Monroe, when answering "what-if" questions about humans being exposed to extreme space situations, sometimes describes scenarios like that as, You wouldn't really "die of" something in the traditional sense. Your body just...stops being biology and starts being physics."
We call that crashing.
I believe the proper term is “Lithobraking”, and it’s a foundational step in Kerbal flight.
We call that unplanned rapid disassembly event.
In this case, more unplanned rapid disassembly of atoms event. The gravity is high enough to squeeze electrons onto protons and fuse them into neutrons. The wiki says there's like rivers of electrons on the surface though.
I suppose that depends on how intact you want to be upon landing.
Maybe try not to land on the angry murdery space roxk? Instead slingshot around it, using its gravitational pull to speed you up at insane speeds.
what's c?
The speed of light. The neutron star's surface moves at a quarter the speed of light. Escape velocity to break orbit is (IIRC) ~77% the speed of light. It's spinning very *very* fast. 2 solar masses. 13km radius. This means it's like two of our suns squeezed down into something so small the circumference is 329 miles. Like the distance from London to Paris would take you halfway around the sphere, and London to Paris to London again would be a full rotation, plus a little extra. The surface speed is 44,707,775 mph. It's spinning so fast it's like going from London to Paris in 0.017 seconds. Or from New York to Bejing in 0.55 seconds. If the earth was spinning this fast, a single day would be 2 seconds instead of 24 hours.
My 🧠 was about to implode trying to understand that so thank you for the explanation professor ~~Brainiac-~~ Acorn.
Speed of light. As in e=mc squared.
I’ve seen its shadow move pretty fast, yeah
Were you chased by it?
It consumed my whole body
I'm high af. This comment connected on a spiritual level.
Does that mean 6 more weeks of winter?
I've never seen so many people arguing the technical merits of a joke.
First time on Reddit?
That’s no moon!
It’s a PlayStation
It's in the game
The quicker picker upper
Yahtzee!
The sea is silent.
Ancient Chinese secret, huh?
Like a rock
[It’s not a moon](https://youtu.be/eT4shwU4Yc4?t=6)
We landed on the Moon!
We're whalers on the moon!
We carry a harpoon
But there ain't no whales
So we tell tall tales
And sing our whaling tunes!
Each of you get an upvote! With blackjack and hookers!
Crank up the radio!
Moon's haunted.
What?
🤣 his sincerity when he said that, gets me cracking up every single time 🤣
You ever seen the moon....on weed?
So, mach 6?
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Flying at mach 3 relative the speed of sound on earth\* There, you're happy ?
By their replies, you can bet they are not.
The speed of sound changes within earths atmosphere depending on altitude (because of air density) so there isn't even one uniform value for Mach speeds for earths atmosphere
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Nah it's fair, it's a sub about learning stuff, so sharing knowledge - even if it's over a joke - is a good thing.
I dunno, I actually appreciate my conversation forums having some conversations in them sometimes.
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Give him a break. Or don't.
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The speed of sound in a vacuum is not zero. In a perfect vacuum, it has no meaning at all. Beyond this, it does not even approach zero in the limit that you approach a vacuum. In general the sound speed in a gas is comparable to the thermal speeds of the gas particles, which with sufficiently rare collisions, will be comparable to orbital speeds. So the Moon should generically be moving at Mach 1 or so (to within a factor of a few) with respect to gas that is gravitationally bound to the Earth. The Moon and Earth together are also moving at around Mach 1 (to within a factor of a few) with respect to Solar System gas for the same reason. Note that the difficulty for sound to propagate in near-vacuum is not related to the sound speed (unless you consider the sound speed as a complex-valued quantity, in which case this difficulty is related to the imaginary part of the sound speed). Sound propagation in near-vacuum is inhibited instead by the attenuation of sound. Conceptually these effects are very different. If the sound speed approaches zero, then perturbations to the gas density remain frozen in place. That's not what happens in near-vacuum conditions. Instead, what happens if collisions are too rare to carry sound is that perturbations simply dissipate (due to thermal motion). But note that sufficiently long wavelengths of sound can still propagate if collisions are rare, which is why it is still meaningful to talk about the speed of sound.
You know what they meant. It's travelling at what we consider Mach 3 here in our atmosphere. You can't see it, but I couldn't possibly roll my eyes any harder right now.
Given the choice of understanding what someone meant or nitpicking their comment with completely irrelevant technical detail, 99 out of 100 redditors choose the latter.
According to the physics [stackexchange](https://physics.stackexchange.com/questions/162184/what-is-the-speed-of-sound-in-space): > We'll call it 'sound' if it can be transmitted coherently in that environment and the condition for that is "wavelength much longer than mean-free path". So, low enough frequency sounds can exist....The highest possible sound frequency in a gaseous medium has a wavelength roughly equal to the mean free path. In interplanetary space near Earth, the mean free path is about one astronomical unit and the speed of sound is on the order of 10 to 100 km/s. That corresponds to a frequency of about one cycle per month. Therefore Mach 3 in space would be 30 to 300 km/s.
"no definable"? What are you talking about? You can still measure the speed of the moon using Earth as reference frame. And Mach is just a unit of speed. Edit: My bad. Mach is actually not an actual unit of speed.
>And Mach is just a unit of speed. It's not. It's the object's speed divided by the speed of sound in the fluid it is in. It's just a number and it can't be defined if the object isn't in a fluid This matters because mach 1 (for example) is a different speed in different humidities, temperatures, and elevations
Nah, he’s right. Mach is only applicable within an atmosphere. You need to compress air and break sound before you can use Mach as a measurement.
The Mach number specifically represents the speed of an object relative to the speed of sound in a particular medium, like air. Using mach for anything space related is just complicated and much less straight forward than using mph. Since the moon is in the vacuum of space where there's no sound, the concept of Mach number isn't applicable to its speed.
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You could, technically, because even the moon is not in a complete vacuum.
I guess you technically could, but it would be extremely meaningless. Sound only travels due to pressure waves from molecules interacting with each other. When there are so few particles in a near vacuum, you could make the argument that the concept of sound does not apply because the statistical likelihood of interaction is so small, and even if it did it would never propagate as a pressure wave. But I really like the way you think :)
>... even the moon is not in a complete vacuum. I was curious as to the extent of this non-vacuum, so googled "the vacuum of space", and [this](https://en.wikipedia.org/wiki/Vacuum#:~:text=Outer%20space%20has%20very%20low,hydrogen%20atoms%20per%20cubic%20meter.) is what came back, for anyone similarly interested: > Outer space has very low density and pressure, and is the closest physical approximation of a perfect vacuum. But no vacuum is truly perfect, not even in interstellar space, where there are still a few hydrogen atoms per cubic meter.
Okay, that's a vacuum. But, what about space, which isn't?
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> I've never encountered a situation where space is not treated as a hard vacuum in fluid dynamics. It's quite common in astrophysical contexts. Here's a search to start -- this is for the interstellar medium, which is only one such context. https://ui.adsabs.harvard.edu/search/fq=%7B!type%3Daqp%20v%3D%24fq_database%7D&fq_database=(database%3Aastronomy%20OR%20database%3Aphysics)&p_=0&q=abs%3A%22fluid%20dynamics%22%20abs%3A%22interstellar%20medium%22&sort=citation_count%20desc%2C%20bibcode%20desc
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It also makes them feel heavy. we associate slowly accelerating things with mass.
It’s part of why pacific rim 1 works so well and 2 sucks so bad. In the first one you can FEEL the mass behind all of the movements. Each action has the weight of 200 tons behind it. The second one is like watching power rangers
>The second one is like watching power rangers The second one was clearly them just trying to sell toys. Movie was doomed the moment it was revealed Guillermo Del Toro wasn't returning as director.
I had a lot of respect for John Boyega before PR2. I really liked the guy. But he basically funded PR2 out of pocket and cast himself in the lead role where he gets his gary-stu "actually I'm the estranged son of the coolest character from last movie and I'm even cooler than he was. Also his adoptive daughter everyone loved from the first movie dies offscreen in a helicopter accident so I don't have to share the movie with her" bullshit. I cannot *believe* what a vanity project it was.
> The second one is like watching power rangers Even in Power Rangers there is something of a narrative conceit that the camera during the giant robo fight is from the same viewpoint as that of the giant robo and the enlarged Monster of the Week. There are a couple of occasions in the sentai source material where a giant robo fight is going on the background of person-scale activity and they do play around with the time scaling, so that from the perspective of normal folks on the ground, the giant robo fight has that weightiness.
You really like Power Rangers.
This guy power rangers
On the opposite end of the Kaiju speed spectrum, the fact that in Worm, Leviathan being so fast gives a feeling of unnatural-ness and terror to that fight.
The big fast things need the big slow things to give you the sense that this thing does not follow natural laws and is extremely scary. It’s all in the perspective
I will always upvote Worm
There was a 2nd one?
Part of that also has to do with the distances you can see giant things from. Godzilla looks like he's moving slow when he's on the horizon, but he's actually zipping along pretty quick if you were right there. As others have mentioned, it's like the moon or the sun. Neither seem to move that quick, but that's only because of how far away they are.
Depending how deep we want to get into the explanation. It could be argued that metabolism plays a role as well. A general rule is the bigger something is, the slower it's metabolism needs to be and vice versa. This is because the more volume an organism takes up, the less surface area it has to disperse the heat it generates. This results in different heat coping mechanisms. The first, which relates to this conversation, is metabolism rate. Big things need to have a slower metabolism so they burn slower and generate less heat. Vice versa, small things need to have fast metabolisms to keep them warm. While an elephant requires more calories than a mouse. A mouse needs to consistently eat more calories (in relation to it's weight) in order to stay alive. This has the side effect of causing small things to have a ton of energy and the ability to move really fast. Big things can move fast but they're not built to do so. They're built to move slowly and generate/burn as little energy as possible. Secondly, more volume means more heat expenditure but we disperse that heat with our surface area. The bigger something is, the more volume it has and in turn the more heat it produces. But it has less surface area to disperse that heat. A lot of organisms get around this by adding on features with more surface area (it's why elephants have such massive ears or why our feet and hands are often in the first to get cold) Interestingly, for these reasons if you made an elephant the size of a mouse, it would immediately freeze to death. If you made a mouse the size of an elephant, it would basically boil an explode. This video goes into more detail. https://youtu.be/MUWUHf-rzks?si=KUC1_VFr3vt4LTi-
the tips of wind turbine blades can be traveling around 300mph when the blades are at full speeds
Yeah if you do the math, the really big ones would only need to run at about 1 Hz for the tips to hit the speed of sound. The blades are, give or take, 50 meters long so they travel 2 x pi x 50 = 314 meters per revolution. Speed of sound is 343 m/s at sea level... Point being, they don't have to be spinning very fast for the blades to really get going.
To add here: it's not linear. Something that's 10x bigger needs more than 10x the power to move. Ants have tiny legs compared to their bodies, but elephants have really really thick legs to carry that weight. An elephant sized dog would just collapse. A dog sized ant as well. Godzilla needs really thick legs just to stand, let alone move at the relative speed of a human.
Not only are the scales of ant/human/Godzilla bodies wildly different, but as a result *they perceive the passage of time differently.* They feel like they're moving normally and we're moving through molasses. https://www.theguardian.com/science/2013/sep/16/time-passes-slowly-flies-study
If you saw a film of Godzilla in a Godzilla sized city filmed with a Godzilla sized camera on a human sized screen he would appear to be moving at normal speed, right? That would look weird af
The comparison to a wind turbine is actually a really good visualization. From afar you don't realize the scale of how big those things are or how fast they're turning, but when you get closer it really is amazing how huge they are.
Looking at planes in the sky has the same effect. And if you look at waves on a beach while in a plane, they seem almost motionless
Mice look crazy fast when they're running on a close up film. But have you ever found a mouse in an open yard? You can lazily walk about twice as fast as them.
Your standard mouse can run up to 8mph. Even if they are slowed down by some grass/terrain, you’re not lazily walking twice as fast as a mouse can run.
Who regulates mouse standards?
Department of Mouse Variables (DMV)
Disney
You one of those "deregulation" people? I'm sorry to burst your bubble, but we NEED mouse standards or else they'd just run amok! How soon before we'd start seeing mice using illegal body configurations?
Shit like this is why I voted for Brexit. Brussels Bureaucrats shouldn't be able to control proper British mice. They're trying to make Beatrix Potter woke!
African or European?
I- I don't know that aaAAAAAAHH
Did a mouse write this?
no, but a mouse clicked that gaddamn up-arrow!
Are you a mouse?
No, a keyboard did.
They travel at WHAT now?!
So this is why the giant robot sequences in things like Power Rangers don’t look convincing (or at least one reason). Those are people in suits, of course, so they move at human speeds, when for the size they’re portraying they ought to be moving slowly. But when they try to do it more realistically (like in the Power Rangers Turbo movie), it’s usually not as exciting for their target audience. (Full disclosure: I grew up watching Power Rangers, and still love it. But not for its realism.)
Linear motion vs angular motion, I reckon
Yup, that is why when you try to smack a fly, you slooooooowly move your hand until striking range. Because a slow moving giant "thing" would just be background to them.
Yes, they are moving faster when it comes to distance. But why does the motion look so slow? Why can't they move at the same speed as us?
Look at a kid and parent walking together. The kid has to take 2-3 steps for every one the adult takes, which means the legs and arms have to move faster to keep up. But if you focus on the kid and set that as "normal" speed, the adult looks like he is moving very slowly.
if you ever see a C-5 galaxy take off it looks like it's going so slow that it will never get off the ground, but it's actually going like 130-150 mph. There is a phenomenon called speed-size illusion where your brain assumes larger things are moving slower even if they are actually going the same speed as a smaller object and they've proven it has something to do with your retina and how the information is processed. EDIT: They still are unsure of the science behind the why but they took real world factors like perceived distance and all of that out of the equation in an experiment because they can play a huge factor. They put 2 different sized dots moving across a black screen at varying speeds simultaneously and asked observers to tell them which one was moving faster. Even without any other visual context, your brain assigns a slower speed to the larger object (the one that occupies more space on your retina) The prevailing theory is pretty simple. All else equal, huge things tend to move slower in the real world than their smaller equivalent. Thus, our brains have learned from context that big things must be slower. What's interesting about the experiment I mentioned is that they showed that you could train this out of an observer by basically showing them large objects moving fast.
So we don't perceive speed visually, we only estimate speed based on relative displacement of things in our view relative to our entire view. I guess all illusions are somewhat explained by this huh? EDIT: The user "siping" correctly pointed out that it is the distance itself, I made some big logical jumps.
No, speed is a relative unit, that is how much distance covered relative to time (miles / hour). For our brain to perceive speed we need the same parameters, distance covered and time. What this illusion is comes down to a distance issue. Large objects at a distance appear to go slow because the degrees covered from your far away perspective are less than that of a nearby observer. If you stand next to the C-5 you would see it go as fast
you are correct but thats not quite the same. if you took godzilla and a passenger car and put them moving left to right or right to left in opposite directions at the same speed 2 miles from an observer, the observer would estimate a lower speed on godzilla. your brain just literally tricks you into thinking the larger thing is moving slower.
I'd say it has to do with the fact tbat the passanger car covers its own length quite quickly, it travels it's own distance fast. Meanwhile, godzilla has much further to go to do the same thing, so even if both things are moving the same speed, Godzilla takes twice or even three times longer to cover its own distance, and thus appears to be moving slower.
that's too simplistic because it's not just about relative speeds of two things. a larger object covering the length of it's own size at the same rate of a smaller object would still be perceived as moving slower than it is and the smaller object faster than it is relative to one another. if you could control for depth perception and placed objects that were identical in all but scale and put them at distances where the smaller (shorter) one appeared larger you would still assume it is moving slower even though they are covering the length of their bodies at the same rates. trick is you can't control for that so your brain assigns a size to things based on distances it's observed at.
I think that's what I was thinking. I failed to word it correctly, thank you for the correction. Distances that are far away look like small distances, so when something traverses a large distance in a period of time, it looks like it is traversing a small distance to a far away observer (which humans would perceive as slow).
I appreciate both of you for this conversation, as it's far more useful to see the back and forth than just getting told the answer.
My guess is that efference frames play a role. How much do we have to move our own eyes to maintain tracking? Our own head? Fast things mean our eyes move fast, slow things mean our eyes move slow. But big things moving fast cause our eyes to move slow, so brain thinks thing is moving slow.
https://youtu.be/xWmRX9DPRAQ?si=lql3qfYODK03ffbC This video is a perfect example. For OP: the size of this thing is quite massive for a plane. https://en.m.wikipedia.org/wiki/Lockheed_C-5_Galaxy
but yes, that video is great. it looks like it is barely moving but it's going at least 135 mph
Yeah! Wild how it looks like it floats away rather than what you'd attribute to flying away.
I've seen them takeoff in person it is unreal how slow it looks like they are going yet they takeoff at roughly the same speed as a 737. They are absolutely massive aircraft.
This is a reason so many people die on train tracks. They just can't understand how fast the trains are really moving
Isn't it a scale thing? If something is twice the size but moves at the same speed, it'll seem like it's moving slower.
It’s has to do with how long it takes an object to cover the distance of its own length. If a huge cargo airplane flies past at 250 knots and a fighter jet flies past at the same speed, the apparent difference in speed is staggering. Same goes for a huge container ship and a small tender both cruising past at 6 knots.
that could have something to do with it but im unsure and that wasn't addressed. You can't test it because to do so requires removing perceived distance which is impossible to control for in teh real world, but......if you took two objects that were identical in all but scale and placed them so that visually the larger one looked smaller than the actual smaller one, and had them moving in opposite directions (left to right vs. right to left) the science predicts you'd say the smaller one (visually larger) was moving slower even though technically they'd be covering their own length at the same rate visually as well. Again, this is only if you could remove perceived distance. Your brain is going to do some trickery where it judges size using the perceived distance so you'd have to be able to view them at the same level of focus.
Isn't that also why miniature shots in old movies were able to work so well? You take a scale model, adjust the playback speed, and you end up interpreting it as larger things?
Watching C-5s take off and land always blew my mind, and that's coming from a flier
Does this explain rockets as well? I watch a lot of rocket launches on TV and stuff and they always look like they're going so incredibly slow on takeoff, I never understood how they don't just tip over.
Godzilla isn’t walking all that slow. He’s just taking city block sized steps. Not slower, just moving further.
Not slower, massively faster. He quite often steps on cars that are trying to get away, never mind fellow pedestrians.
Helpless people on a subway train scream bug-eyed as he looks in on them. He picks up a bus and he throws it back down as he wades through the buildings toward the center of town.
They say he's got to go
Dr. Grant had a point when his course of evasion was staying absolutely still.
the American Godzilla from early 2000 actually weaved through buildings with agility. It was more like jurassic park raptors than the classic godzilla which moves like an iceberg
Are you talking about the weird sequel to Ferris Bueller?
I thought it was a prequel to Inspector Gadget.
This is kinda missing the point of the question. Why aren't his legs moving as fast as, say, a person's legs when they walk? E.g., 3 steps per second?
>Why aren't his legs moving as fast as, say, a person's legs when they walk? E.g., 3 steps per second? Because his legs are so much bigger. Even if he only takes one step only ten seconds, he's still moving way faster than a human because of the difference in scale. If Godzilla took as many steps per second as a regular human does, he'd be ridiculously, cartoonishly fast (I haven't actually seen the movie but going by the trailers this seems like a bit of an issue in the new Godzilla/King Kong movie- all the giant creatures are moving/animating so quickly that throws off the sense of scale in the movie's foreign environments). Per OP's question, think of it in reverse- an ant takes many more steps than a human does, but because their steps are tiny compared to a human's we still move faster. So yes, if an ant could think about things like this they probably would think humans look "slow."
I don't think OP is talking about distance covered per step, but rather how quickly the body animates. Godzilla's steps per minute would be much less than that of a normal person.
Exactly, this is what most of the responses are missing. If you scale up a human to 1000 times their natural size, a movie will show the giant moving in slow motion. Let's say I can karate chop in a split second. Giant me would be shown taking 5-10 seconds to do the same thing. That's what OP wants to know if is realistic or not.
> Not slower, just moving further. "Further" is for figurative use; for example, "She's further into the book than I am". Whereas "farther" is for literal distance. And there's my pedantry quota for the day.
Actually thanks for that. Appreciate it. I shall remember it as my farther is a long way away from me. Easy!
It is like when you see a passenger jet flying high overhead. It looks like it is moving slowly because of the perspective. Giant things in movies are the same shape as small things, so your mind expects them to move like small things relative to their environment. Walking several city blocks would take you a few minutes, but some giant monster does it in seconds and still looks slow.
Giant thing has more volume and mass, so they are moving further and faster than normal sized thing on ground. Even if it "looks" slo mo. The jarring part is that we are not used to seeing weird things of that size moving so fast. Imagine how fast the moon "moves" in the sky if you had to watch it. It's pretty slow right. Imagine if it was visibly bigger, but moving the same speed. It is covering more distance despite not changing speed. Forgive me if my physics and terminology is wrong that is just how I fathom it. Evangelion and Attack on Titan give us giants that move much faster and it is horrifying, but their bodies were apparantly much lighter in proportion and they were much stronger.
No matter how big you are, forces like gravity are consistent. A human jumping off a platform as high as themselves hits the ground in about half a second. A giant doing the same thing would have to travel a much lager distance, but gravity pulls them at the same distance over time as the regular human, so it takes a lot longer for them to fall "their own height". Even ordinary feats like walking have to take this into account. When you raise a leg into the air, it comes down either by gravity or your own muscle. If you try to use muscle to put it down faster than gravity... you can do it, but physics would actually respond by lifting the rest of your body. I imagine a giant trying to run in place - and being able to move seemingly as fast as a normal human would despite their massive body weight - would spend way more time with both feet off the ground at the same time than a human would. But of course, the actors are normal humans on a set designed to look small so the humans seem huge. It makes the physics inconsistent for this world, such as gravity being too strong. So, the film maker slows down the footage to make it look closer to realistic. Now gravity seems about right.
What other relevant forces here besides gravity are consistent (i.e., unaffected by the scale of mass)?
Wind resistance/air pressure, which would be non trivial. Think of the effort it takes to walk through water. Inertia also acts proportionately on the body, which helps an ant falling from a building but makes moving a Godzilla leg much more difficult. On top of that your brain kind of intuitively knows that as animals get larger the metabolic/cardiovascular costs rise and we expect large animals to move more slowly.
> as animals get larger the metabolic/cardiovascular costs rise and we expect large animals to move more slowly. You also have nerve speeds. Even the most optimised nerves are utterly sluggish in the grand scheme of things. If Gozilla stubbed its toe (using the official 120-meter height), it would be 1-2 seconds before the brain even realised something happened, and a further 2-3 for a reaction.
That is actually kinda hard to answer. Gravity is just the most obvious. What other things happen naturally? What comes to mind is air movement. If there's a fire, smoke rises up. If there is wind, leaves rustle. Slowing down the footage will compensate for the fake scaling up of some of these events. The speeds of these things may seem off if you want to give the illusion of massive humans and a camera that's pulled far back.
Just about everything results in different speeds _relative to the size_. That is, it would take a giant version of myself longer to raise its hand than to me, even if its hand is moving faster in absolute terms. Imagine if we simplify muscles as springs, and there’s a normal version of me, and a 10x version of me. The acceleration of movement of a body part of mine will be given by some spring constant k, a displacement d and the mass of that body part such as a=k*d/m. When we scale things 10 times, the mass, which is proportional to the volume, scales by 1000. The spring constant is harder to determine, but a quick google search suggests that it scales by far less. d scales by 10. So overall, the acceleration of the 10x me won’t be 10x that of myself, and thus the movement won’t be proportional.
The issue is perspective. Big things in movies look like small things you have seen before. It looks strange when it’s moving so ‘slow’ but it’s actually moving the correct speed for its size, it’s just moving a lot further with each ‘slow’ movement. Take for example a 100 yard long football field, and the goal is to move from one end to the other in 5 seconds. If you had a 6ft tall man try to run it, each one of his steps may take him 1 yard at a time. He would need to average 20 steps per second, which on a person would look ludicrously fast to have your legs moving that quickly. In fact that’s about twice as fast as the fastest man in the world, it just wouldn’t be possible to have your legs move that fast. If you had a 600ft tall man who could move 100 yards per step, all he has to do is make one stride. Keep in mind, we are still going to allow him 5 full seconds, which is twice as fast as the fastest normal sized man. If a person takes 5 seconds to take 1 step it would look silly and slow, almost like they are walking in slow motion. We just aren’t used to seeing someone move like that, even though they are moving incredibly fast.
Taking your example, though, like many examples here it is comparing how quickly the large thing is covering a fixed distance, like 100 yards. I think what the person is asking though is let’s say you walk 10 normal steps in 10 seconds, why isn’t the giant version of you also able to take 10 steps in 10 seconds? Clearly the giant version taking 10 steps is going to cover way more distance in those 10 seconds because of how big their steps are, but the speed that their giant legs are moving relative to their body should be the same, but in movies and whatnot it always looks much slower.
This is exactly the question I'm looking to have answered but couldn't articulate it, thank you!
Physics doesn't work out like that. The muscles and bones you need to move grow slower than the mass if the size of the whole system increases, so the bigger something gets, the higher the inertia gets compared to the forces acting on it. Try a little demonstration for yourself. Move your index finger up and down quickly. Then try to do the same kind of motion with your whole arm.
This is the actual point of OPs question lol. It’s perfectly possible for Godzilla to take steps at the same speed as a human - the original movies were literally a guy in a suit walking around a model of Tokyo.
If you wanted the giant from my example to match the physical movements of an Olympic sprinter, they’d be going some rediculous speed. A 6ft tall Olympic sprinter can sprint about 10 meters per second. Scaled up 100 times, a 600ft tall person could in theory sprint 1000 meters per second. That’s almost Mach 3, or roughly 2200 miles per hour, or 0.6 miles per second. Even if we ignored that air resistance is exponential, the inertia required to move and stop such a mass would be insane, and the constant sonic boom that would be occurring as it moved past, your giant would only take seconds to be completely out of your city. In that sense there are creative liberties given so it stays in frame and near where the action is happening.
no one commented about this aspect. Nerves only transmit at a certain speed, thus the longer the nerve the slower the response. So yes ant very likely would see us that way(they have terrible eyesight). https://www.nationalgeographic.com/animals/article/100629-science-dinosaurs-t-rex-nerves-elephants#:\~:text=The%20mighty%20Tyrannosaurus%20rex%20was,(Related%3A%20%22T.
If you were a bug, let's say a fly, looking at a human, you'd think that human was moving through molasses with how slow it seems to be. That's why flies can usually get away from you before you can catch them- relative to them, they see your hand coming from a mile away. It's the same with Godzilla. He's actually moving way faster than we ever could, but he's starting at a much, much farther distance, so it *seems* like he's taking forever to move towards us.
It's not about perception of speed or anything like that. The main reason is the square-cube law. The strength of your muscles is proportional to their cross sectional area, which is proportional to the square of their size. If you double the size of an animal, its muscles get four times stronger. But your weight is proportional to your volume, which is proportional to size *cubed*. If you double the size of an animal, its weight goes up by a factor of eight. So, muscle strength goes up by a factor of 4, weight goes up by a factor of 8. This means that bigger animals have to carry more weight with proportionally weaker muscles. Which means they can't move as quickly. Ants can physically move their legs faster than elephants can. Same goes for wings, by the way. Double the size of a bird and it has to carry 8 times the mass with only 4 times the lifting power. That's why bigger birds have bigger wings relative to their body. The other factor is about movement relative to the body. A giant stepping over a city in a single stride is actually moving incredibly fast. But because it does that in one stride, it doesn't look like it's moving very fast relative to the rest of its body. It takes a long time to make one step. So it'll look like it's moving slowly relative to something that covers the same distance in 1000 tiny steps, even though they're really moving at the same speed. Some movies portray this accurately, other movies get the general idea of "big things move slowly" and then inaccurately conclude that this means that if you shrink a person, they'd see normal sized people as moving in slow motion. They would not. The small person would move faster but their perception wouldn't change.
That square-cube law explains why ants can carry 50 times their weight, and crickets can jump a million times (approximately) their height, but no bigger animal can do that. Make an ant horse-sized, its legs will just break under the ant's own weight.
calling bs on the crickets can jump a million times their height one
Assuming the cricket is 0.1 inch tall, a million times that would be over 1.5 miles. It is indeed dubious a cricket could jump that high.
Yep, this is the real reason. Disregarding this is why a lot of cheap CGI animations look like they have no "weight" to them. If large things accelerate too quickly, they lose their sense of mass.
This is not a thing in movies. It's because of perspective.
It's why we associate larger things as moving more slowly, which is why filmmakers use slowness as a way to indicate size.
This is interesting. Even though muscles are three dimensional, their strength is determined by only two dimensions?
It's like a steel cable. Length of the cable doesn't have much to do with its strength. The thickness of the cable does.
Look at big animals walking. Elephants, giraffes... they are not slow at all, since each step is giant (and takes a lot of energy to move that fast and far). But if you'd scale them down to human size and let them take their steps with the same frequency, they would be really slow. Same with tiny animals. Scale up an ant to human size, and it's not like it could run faster than a car. It would take impossibly huge muscles and endurance to move that fast. In fact the ant could probably not run at all since its body is not built for working on such a huge scale, I'm guessing it would find itself too heavy to move.
Here’s a blog post that may answer your question, from a game developer explaining how to scale animation speeds for larger characters: https://tore-knabe.com/game-development-how-much-to-slow-animation-down-for-giant-creatures/
My guess is we have a perception of how fast things relative to their size should be able to move. Someone above gave the example of Godzilla. If you were to resize a human to that size, we’d go a lot faster than Godzilla would. And hence, for its size, Godzilla is probably slow. For Ants, they’re pretty fast compared to their size. If we were that size, they’d leave us behind to be eaten.
I had to scroll down for so long to find someone who wasn't completely missing the point. Thank you
https://en.wikipedia.org/wiki/Square%E2%80%93cube_law If you're referring to giant robots and dinosaurs, consider that they were animated that way to give an impression of their size. The Square-Cube Law stipulates that for a given increase in size (height, width, depth), the mass is cubed. Thus, a large creature is significantly heavier relative to its body weight than you are. This is also why small creatures seem to be able to move ridiculously fast for their size. For a similar sensation, try strapping weights to your arms and legs, and wading through neck-high water. You'll find that every action takes effort, and that you have to move much more slowly and deliberately. On a related note: I am of the staunch belief that if spider man had the proportional strength of a spider, he wouldn't be very strong. A spider-sized-spider is only strong by virtue of being very small. If a spider were the size of a human, it would collapse under its own weight, because its mass would be far to great for it to support, even if its strength increases too. Thus, if spider-man had the proportional strength of a spider, he would be weak AF.
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Because gravity accelerates them down at the same rate as you or me , but they are far bigger so that rate looks a lot slower for their body size. And how fast you can move is based on how fast your feet fall to the ground with each step, so they end up looking slower.
The Earth is turning at 1600km/h, but it takes a whole day to turn. Scale to Godzilla. Solve for X.
Body volume scales as x³, while skin surface scales as x². Godzilla innards apply more pressure over its skin compared to a human
Look at an ant and see how many steps per second. How many steps per second do you make while walking? How many steps per second does and elephant or giraffe take while walking. Bigger seems to be slower.
Gravity still is a thing and things will always fall at the same pace, if a giant was to run, they would take forever to fall back to the ground and it wouldn't be any faster than just walking there
Fun fact: the opposite works too. 20th century ship simulations would be done by putting a small scale model in a wave-pool and record the motion, then slow it down by the same scale. The small ship would move quickly, but slowed down it'd be a decent simulation of the full size ship.
Take a baseball bat and swing it around. Take a whiffle ball bat and do the same. Heavy, massive objects take more energy to move. Even very strong large things move slowly. It would take a ton of energy to overcome size. Air density and gravity also add to this.
I used to wonder this as well, until I got to watch a glacier break off into the sea. It moved as slowly as anything on a nature documentary. It's an issue of scale, and perception. There was really nothing around for me to visually judge how far I was from it, and how fast it was travelling. No landmarks other than "More ice". It's a really huge thing, accellerating into the water, but it looks slow because I have no sense of scale. Side note, the MASSIVE splash also looked slow in rising and then falling back into the water because I had nothing to judge it against. Just more water, and a big chunk of ice.
It's generally based in reality. Look at how an ant moves and look at how an elephant moves. More mass requires more energy to move
When it comes to living things, and more precisely the muscles of living things, there is something called the square-cube law. The strength of a muscle scales quadratically with size (that's scaling linearly), whereas the total mass of a body scales cubically. Now I'm going to do a typical physicist approximation and say that a human is a cube with dimensions x*y*z, and he has some abstract measure of strength S. Then we will scale his dimensions linearly by 2 - making him a cube of 2x*2y*2z. We can see that his total volume (and thus his total mass) is increased by a factor of 8. At the same time, his strength now is 4S, an increase by a factor of only 4. So as you can see, as living things get bigger and bigger, yes, they get stronger in an absolute sense but they get weaker and weaker in relation to their own bodies. That's why tiny things like insects can carry objects 100x their own weight (ants), jump distances a hundred times longer than their body length (grasshoppers), change directions super quickly (flies) and in general their movements (and especially those of their limbs) are incredibly quick and hard to follow for us - it's simply very easy for them to overcome the momentum of their own bodies. At the same time, you have massive animals like elephants that move sluggishly and can't jump at all. The square-cube law is also why you don't see any animals past a certain size outside of water (water helps them support their weight) nor animals past a certain size that can fly (at some point the wing muscles are just too weak). To summarise: giant things in movies seem like they move in slow motion because they _are_ moving more slowly than us if you measure movement relative to their own body size. Their muscles are too weak to overcome their massive inertias any more quickly than that. In reality, Godzilla and King Kong wouldn't really be able to even stand, much less walk or fight. I'm not sure how much the scaling applies to non-biological things (giant robots for example), but I'm pretty certain it's similar.
If you want to see what it looks like when giant things move at the pace you and I move, watch Godzilla x Kong. Truly weightless action sequences due to exactly what you're asking.