APS News

Zero Gravity: The Lighter Side of Science

An Alternative Theory for Perpetual Motion

We at APS News are continually entertained and enlightened by the various and sundry tidbits we find floating in the ether of the Internet, especially when we discover heretofore unsuspected scientific theories. An un-named British magazine supposedly held a competition recently, inviting its readers to submit new scientific theories on ANY subject. Below is the winner, on the subject of perpetual motion:

When a cat is dropped, it always lands on its feet, and when toast is dropped, it always lands buttered side down. Therefore, if a slice of toast is strapped to a cat's back, buttered side up, and the animal is then dropped, the two opposing forces will cause it to hover, spinning inches above the ground. If enough toast-laden felines were used, they could form the basis of a high-speed monorail system.

The magazine then got this letter in reply from one of the recipients:

I've been thinking about this cat/toast business for a while. In the buttered toast case, it's the butter that causes it to land buttered side down - it doesn't have to be toast, the theory works equally well with Jacob's crackers. So to save money you just miss out the toast - and butter the cats. Also, should there be an imbalance between the effects of cat and butter, there are other substances that have a stronger affinity for carpet.

Probability of carpet impact is determined by the following simple formula: p = s * t(t)/t(c) where p is the probability of carpet impact, and s is the "stain" value of the toast-covering substance - an indicator of the effectiveness of the toast topping in permanently staining the carpet. Chicken Tikka Masala, for example, has a very high s value, while the s value of water is zero. t(c) and t(t) indicate the tone of the carpet and topping - the value of p being strongly related to the relationship between the color of the carpet and topping, as even chicken tikka masala won't cause a permanent and obvious stain if the carpet is the same color.

So it is obvious that the probability of carpet impact is maximized if you use chicken tikka masala and a white carpet - in fact this combination gives a "p" value of one, which is the same as the probability of a cat landing on its feet.

Therefore a cat with chicken tikka masala on its back will be certain to hover in mid air, while there could be problems with buttered toast as the toast may fall off the cat, causing a terrible monorail crash resulting in nauseating images of members of the royal family visiting accident victims in hospital, and politicians saying it wouldn't have happened if their party was in power as there would have been more investment in cat-toast glue research.

It is in the interests not only of public safety but also public sanity if the buttered toast on cats idea is scrapped, to be replaced by a monorail powered by cats smeared with chicken tikka masala floating above a rail made from white shag pile carpet.

Net myth, or genuine magazine contest? We would be most interested to hear from any of our readers as to the origin of this tantalizing theory, as well as whether its proponents have managed to snag from NSF funding to pursue their research.

APS encourages the redistribution of the materials included in this newspaper provided that attribution to the source is noted and the materials are not truncated or changed.

Editor: Alan Chodos
Associate Editor: Jennifer Ouellette