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There have been instances where cats fall from more than 30 stories high, yet escape alive! The record was a cat which fell 32 floors, yet only suffered only slight damage to its body and lost a tooth. How was this possible? Logically speaking, even if a cat could right itself during a fall, how could it cushion such a huge impact? I would like to know why this happens.

Qmechanic
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QuIcKmAtHs
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    I'm voting to close this question as off-topic because this really isn't a physics question. How the cat survives a fall is not a question about physics concepts, but about feline anatomy. Maybe suitable for Biology SE ? – StephenG - Help Ukraine Jan 07 '18 at 05:52
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    Hint: google square-cube law and terminal velocity. Humans also occasionally survive falls long enough to reach terminal velocity. – The Photon Jan 07 '18 at 06:09
  • No @StephenG . I found this problem in the book called the fundamentals of physics by Halliday, Resnick, and Walker. It has something to do with terminal velocity as The Photon Pointer out. I think I am beginning to understand. – QuIcKmAtHs Jan 07 '18 at 06:23
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    Honestly I think that this is one of those common instances where a question in a book is perhaps an oversimplification of a complex problem. People have been known to survive falls from insane heights (like thousands of feet), but exceptional cases can't be explained by such simple methods. – StephenG - Help Ukraine Jan 07 '18 at 07:37
  • @StephenG There is A LOT about physics in it. 1) They change their orientation while falling with tricky movements 2) They maximize their drag 3) Their surface-to mass ratio is much higher as ours. I think anatomy has a little effect here, if their internal organs lethally damage on splashdown, also they die as we. But it happens much lesser as to us. – peterh Jan 07 '18 at 17:48
  • I'd point out you can make the "there's a lot of physics about it" argument about practically anything but pure mathematics. (1) is anatomy, (2) I'm not aware of any proof of this statement about drag - e.g. can you say that another orientation is not maximizing drag ? and (3) their surface-to-mass ratio won't prevent injury (as you seem to agree). The danger here is making correlations that are incomplete or which seem correct but are a result of incomplete analysis. – StephenG - Help Ukraine Jan 07 '18 at 18:39
  • More on falling cats. – Qmechanic Jan 07 '18 at 18:42

1 Answers1

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Here is the cat righting reflex

In addition to the righting reflex, cats have other features that reduce damage from a fall. Their small size, light bone structure, and thick fur decrease their terminal velocity. While falling, a cat spreads out its body to increase drag. An average-sized cat with its limbs extended achieves a terminal velocity of about 60 mph (97 km/h), while an average-sized man reaches a terminal velocity of about 120 mph (190 km/h). A 2003 study of feline high-rise syndrome found that cats 'orient [their] limbs horizontally after achieving maximum velocity so that the impact is more evenly distributed throughout the body. The study authors speculated that after falling five stories the cats reached terminal velocity and thereafter relaxed and spread their bodies to increase drag.

On injuries:

With their righting reflex, cats often land uninjured. However, this is not always the case, since cats can still break bones or die from extreme falls. In a 1987 study, published in the Journal of the American Veterinary Medical Association, of 132 cats that were brought into the New York Animal Medical Center after having fallen from buildings, it was found that the injuries per cat increased depending on the height fallen up to seven stories, but decreased above seven stories.

The study was critiqued that dead cats are not brought to the vets, so the statistics is not reliable. It is about surviving cats from falls. Still that was a very lucky cat, but its velocity was not higher than falling from a 5th floor or so .

anna v
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  • This is called Survivor Bias and kudos for mentioning that (possible) flaw in the study. – StephenG - Help Ukraine Jan 07 '18 at 07:32
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    No. While there are contrasting cases, the number of survivors is too large to be ignored – QuIcKmAtHs Jan 07 '18 at 10:03
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    @XcoderX That's precisely the kind of fallacy that leads to cases of survivor bias. The correct analysis would focus on the failure mode. As Anna-v pointed out the main study did not investigate causes of death, which is the real problem. – StephenG - Help Ukraine Jan 07 '18 at 18:44
  • @StephenG and XcoderX, the statistically correct experiment would be horrible. One will not throw cats from floors and count up the type of injuries and deaths in percentages versus height. Declaring deaths of cats is not obligatory, so no statistics is available. One could make an effigy, with instruments and record damages and calibrate the results with surviving cats, but it is a lot of trouble and expense for what? – anna v Jan 07 '18 at 19:59
  • While I personally don't like cats (dog person) I'm not actually keen on throwing them off tall building to check for dead cats. However, if someone wants to publish a study on this subject it behooves them to try and investigate actual causes of death and not try and work only from survivors. I'm simply saying the study is invalid because it doesn't deal with this correctly. With humans we invested e.g. crash test dummies, so presumably something similar could be done with cats - honestly, this is why we need Mythbusters. :-) – StephenG - Help Ukraine Jan 07 '18 at 20:10