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It is a general statement that cats tend to fall on their feet. How far is this is a valid statement? If I were to drop a cat from 50 meters height, feet up(hypothetically), would it still land on its feet? But would that violate the angular momentum conservation (if initially the cat has zero spin when dropped) and the law of Inertia?

Qmechanic
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Abhinav
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    Cats do fall on their feet: there are slow-motion films showing how they do this. This obviously does not violate angular momentum conservation. In particular remember that the conservation rule applies to the whole cat: if it can temporarily arrange for part of it to have some angular momentum (tail) the rest of it will have equal and opposite AM and will thus spin. Also note that cats are quite small so they live in a world where air-resistance can be usefully exploited. Don't drop a cat from 50m up: it will break bones. –  Mar 28 '16 at 11:15
  • Hence the word hypothetically – Abhinav Mar 28 '16 at 11:19
  • I feel like this has been asked and answered already on this site, but the mobile interface isn't quite functional in this respect. – Kyle Kanos Mar 28 '16 at 11:21
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    It's addressed in the question on How do astronauts turn in space?. – lemon Mar 28 '16 at 11:34
  • @Abhinav: sorry, I didn't mean to imply you would. It is possible to do this experiment from (much) lower heights if you have a cat you are on good terms with. The interesting thing is that they never land on their side: there's a minimum height below which they don't even try (this experiment needs to be done over a very soft surface like a bed). And I am not suggesting anyone do these experiments unless it is very clear no distress or harm is caused to the animal! –  Mar 28 '16 at 11:39
  • Possible duplicates: http://physics.stackexchange.com/q/24632/2451 , http://physics.stackexchange.com/q/32882/2451 , http://physics.stackexchange.com/q/88322/2451 and links therein. – Qmechanic Mar 28 '16 at 11:46
  • Here is a nice video of a cat falling with an explanation. https://www.youtube.com/watch?v=RtWbpyjJqrU – Farcher Mar 28 '16 at 11:49
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    I'm voting to close this question as off-topic because it would belong on a Biomechanics.SE site if such existed – Carl Witthoft Mar 28 '16 at 11:49
  • @CarlWitthoft: I'd argue against that: first of all there isn't such a site, and secondly it is actually a physics question I think. I agree that it may be a duplicate, but that's a different question. –  Mar 28 '16 at 14:52

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This has been well studied.

Cats use their tails to flip themselves around. Initially, the inertia of the tail matters. After a short time, the wind resistance of the tail becomes significant.

Put another way, cat's right themselves using angular momentum, then keep them selves that way using aerodynamics.

Olin Lathrop
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    Actually housecats (Felis Sylvestris) don't really use, or need their tail to flip. The wonderful little animation on the "Cat Righting Reflex" wiki shows how a cat with equal inertia matrices for forward and hinder halves flips. My own cat has been tailless since 2004 when she lost her tail in an accident and neither now has any difficulty making the reflex and took almost no time to learn it again after her tail had to be amputated. "Tailless" flipping means that the rotation is confined to one axis .. – Selene Routley Mar 28 '16 at 12:09
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    ... but some tree dwelling cats, such as the Asian Marbled Cat have heavy, clublike tails that are important for their righting reflex because they freely re-orient themselves about all three axes as they dive bomb their prey or sail from one tree to the next. – Selene Routley Mar 28 '16 at 12:11