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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?

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marked as duplicate by Carl Witthoft, user36790, Qmechanic Mar 28 '16 at 12:54

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    $\begingroup$ 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. $\endgroup$ – tfb Mar 28 '16 at 11:15
  • $\begingroup$ Hence the word hypothetically $\endgroup$ – Abhinav Mar 28 '16 at 11:19
  • $\begingroup$ I feel like this has been asked and answered already on this site, but the mobile interface isn't quite functional in this respect. $\endgroup$ – Kyle Kanos Mar 28 '16 at 11:21
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    $\begingroup$ It's addressed in the question on How do astronauts turn in space?. $\endgroup$ – lemon Mar 28 '16 at 11:34
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    $\begingroup$ I'm voting to close this question as off-topic because it would belong on a Biomechanics.SE site if such existed $\endgroup$ – Carl Witthoft Mar 28 '16 at 11:49
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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.

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    $\begingroup$ 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 .. $\endgroup$ – WetSavannaAnimal Mar 28 '16 at 12:09
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    $\begingroup$ ... 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. $\endgroup$ – WetSavannaAnimal Mar 28 '16 at 12:11

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