Newton’s First Law is best illustrated by cats.
Originally shared by DaFreak
It’s that day of the week again… #Caturday :p
Recent Comments
Newton’s First Law is best illustrated by cats.
This entry was posted in Rajini Rao. Bookmark the permalink.
madame scientist's not-so-mad musings 
And if you apply a force, it will bite you 馃檪 I tried this experiment on a dog growing up, I will never forget that experience. Protect yourself before you try this experiment 馃檪
Chris Veerabadran , every action has an equal and opposite reaction?
Rajini Rao Very true 馃檪
+ An object scratching a dissimilar object tends to stay the course unless acted upon by spray-bottle water-force.
Corollary: The subject of the object’s scratch will tend to object and attempt to subjugate the objectee.
Marc, you are employing a version of the Pike pepper-spray method for the cats 馃檪
Calm down Chris Veerabadran , Marc was only using a food product.
Rajini Rao Maybe food for Homo sapiens, but definitely cats hate water 馃檪 If you guys employ water, then you will become infamous like Pike in their world 馃檪
oh oh nice picture…i like it
what about an object in motion?
nice …………….
nice
lucky cat
Brian Mahon Ever tried to convince a cat to stop scratching you?
this is what we do at class room na
taking a rest
very clever…like you…
What amazes me most about cats movements is their ability to rotate their bodies while they’re in free fall, so they can land on their paws, and they do it all with a zero angular momentum.
That’s cos cats are like little parachutes when falling.. So the torque due to air drag provides the angular momentum..
Manish Goregaokar, this is not the case. I think it was published an article about it in Scientific American some years ago, and I think it was also explained in “Quirks and Quarks”, a program of CBC Radio. Cats can twist their backbone so each half of their body can point downwards at each side. They manage not to go back to the original position by means of a series of alternating stretches and bending of each pair of paws from their twisting axis. At the end, those cats don’t have any angular momentum (they don’t rotate), but their belly and paws are facing down.
Edit: What cats straighten and bend are actually their backs.
In this video it can be clearly appreciated: http://video.nationalgeographic.com/video/player/animals/mammals-animals/cats/cats_domestic_ninelives.html
I’ve found some references:
1. Frohlich, Cliff. The Physics of Somersaulting and Twisting. Scientific American, March 1980, pp. 164-174. http://www.physics.utoronto.ca/~phy189h1/Physics%20of%20Somersaults%20and%20Twists.pdf
An old article of Scientific American in PDF. I don`t think it was this one where I read it, but the process is explained with detail
2. Nguyen, Huy D. How does a cat Always Land on Its Feet? Georgia Institute of Technology, School of Medical Engineering. http://helix.gatech.edu/Classes/ME3760/1998Q3/Projects/Nguyen/
3. Gollin, George. The Physics of Dance (transparencies for a presentation I’ve given at Hope College on the Physics of Dance). Department of Physics, High Energy Physics, University of Illinois at Urbana-Chanpaign. November 1, 1996, and October 24, 1997.
http://www.hep.uiuc.edu/home/g-gollin/dance/dance_physics.html
Ever see a falling cat right itself? The cat has zero angular momentum at all times, but somehow manages to turn over. It works like this:
Upside-down cat curves its back “the easy way.”
Cat straightens its back while bending around its middle to its right.
Cat comes out of its bend-to-the-right while arching its back “the hard way.”
Cat straightens its back while bending around its middle to its left.
Cat comes out of its bend-to-the-left while curving its back “the easy way.”__Here’s a diagram: http://www.hep.uiuc.edu/home/g-gollin/dance/Image57.gif
Dancers can also perform zero-angular-momentum turns. Some are catlike, some not…
In some moves, the body parts which carry the initial angular momentum change during the course of the turn. An example: a tour jet茅. The angular momentum associated with the raising of the left leg (1) is taken up by the trunk and arms (2), then the left leg (3), then both legs (4).
http://www.hep.uiuc.edu/home/g-gollin/dance/Image58.gif
The diagram is based on photos in Laws’ and Harvey’s book.
4. Cat righting reflex. English Wikipedia. http://en.wikipedia.org/wiki/Cat_righting_reflex
5. Falling cat problem. English Wikipedia. http://en.wikipedia.org/wiki/Falling_cat_problem
http://upload.wikimedia.org/wikipedia/commons/7/78/Cat_fall_150x300_6fps.gif
6. High-rise syndrome. English Wikipedia. http://en.wikipedia.org/wiki/High-rise_syndrome
7. Video: A Cat’s Nine Lives. National Geographic
http://video.nationalgeographic.com/video/player/animals/mammals-animals/cats/cats_domestic_ninelives.html
Do cats always land on their feet? High-speed photography shows us the answer.
8. Video: Why Cats Land on Their Feet. National Geographic News. September 28, 2006. http://news.nationalgeographic.com/news/2006/09/060928-cats-land-video.html
It might sound like a form of urban anxiety, but high-rise syndrome is actually a serious problem for cats in the city. Adventurous felines don’t always look before they leap, and many wind up in emergency care after they go careening through unscreened windows.
But a mystery unfolded when doctors treating these “high-rise kitties” noticed a pattern: Cats that fell from great heights were less injured than those that took a modest dive.
See slow-motion cameras reveal how a falling cat manages to land on its feet, and find out why鈥攆or these furry acrobats鈥攖he higher they are, the better they fall.
9. Wells, Virginia. Why Cats Land on Their Feet. http://www.petplace.com/cats/why-cats-land-on-their-feet/page1.aspx
10. Deveshvar, Manisha. Why do Cats Always Land on Their Feet? http://www.pitara.com/discover/5wh/online.asp?story=157
11. The miracle of the falling cat. Brazillion Thoughts.
http://scienceblogs.com.br/brazillion/2009/06/the_miracle_of_the_falling_cat/
12. Do cats always land unharmed on their feet, no matter how far they fall? The Straight Dope. July 19, 1996. http://www.straightdope.com/columns/read/1143/do-cats-always-land-unharmed-on-their-feet-no-matter-how-far-they-fall
13. Allen, Patricia E. The Physics of Cats. Appalachian State University. Tuesday, Jan 27, 2004. http://www.oapt.ca/aapt/2004_winter_meeting/The_Physics_of_Cats.pdf
Brief with some references of experiments studying to cat falls.
14. Galli, John Ronald. Angular momentum conservation and the cat twist. The Physics Teacher. September 1995. Volume 33, Issue 6, pp. 404 http://dx.doi.org/10.1119/1.2344252
15. Diamond, Jared M. Why cats have nine lives. Nature 332, 586-587 (14 April 1988) | doi:10.1038/332586a0 http://www.nature.com/nature/journal/v332/n6165/pdf/332586a0.pdf
16. Kane, T.R., Scher, M.P. A dynamical explanation of the falling cat phenomenon. International Journal of Solids and Structures. Volume 5, Issue 7, July 1969, Pages 663-666 http://www.sciencedirect.com/science/article/pii/0020768369900869
17. Vnuk D. et al. Feline high-rise syndrome: 119 cases (1998-2001). Journal of Feline Medicine & Surgery. Volume 6, Issue 5, October 2004, Pages 305-312 http://www.sciencedirect.com/science/article/pii/S1098612X03001219
18. Whitney W.O., Mehlhaff C.J. High-rise syndrome in cats. J Am Vet Med Assoc. 1987 Dec 1;191(11):1399-403. http://www.ncbi.nlm.nih.gov/pubmed/3692980
Aah, I see, thanks!
But i’m quite sure that, once aligned, cats do act like parachutes…
Cute