Is that realistic? Do ants see us like that?
In: Physics
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.
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