Why do giant things in movies move in slow motion?

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Is that realistic? Do ants see us like that?

In: Physics

34 Answers

Anonymous 0 Comments

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.

Anonymous 0 Comments

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.

Anonymous 0 Comments

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 actualyl 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.

Anonymous 0 Comments

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.

Anonymous 0 Comments

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.

Anonymous 0 Comments

Godzilla isn’t walking all that slow.
He’s just taking city block sized steps.

Not slower, just moving further.

Anonymous 0 Comments

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.

Anonymous 0 Comments

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.

Anonymous 0 Comments

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.

Anonymous 0 Comments

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.