Is This Perpetual Motion Machine Really Possible?

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SUMMARY

The discussion centers on the feasibility of a perpetual motion machine involving a cat and a piece of toast. The concept suggests that the cat, when tossed, will always land on its feet while the toast lands butter side down, creating a perpetual spin. However, participants conclude that this idea contradicts the laws of physics, particularly due to the cat's mortality and the statistical probabilities of toast landing butter side down, which depend on the height of the table and the size of the toast. The discussion also references experiments on toast dropping, highlighting flaws in methodology and the importance of consistent testing conditions.

PREREQUISITES
  • Understanding of basic physics principles, particularly gravity and motion.
  • Familiarity with statistical probability concepts.
  • Knowledge of experimental design and methodology.
  • Awareness of common myths in science, such as the toast landing butter side down.
NEXT STEPS
  • Research the laws of thermodynamics and their implications on perpetual motion machines.
  • Explore statistical analysis techniques relevant to experimental outcomes.
  • Investigate the physics of motion and gravity as they pertain to falling objects.
  • Review scientific methodologies for conducting experiments and ensuring consistent results.
USEFUL FOR

This discussion is beneficial for physics enthusiasts, educators, and anyone interested in the intersection of science and popular myths, particularly in understanding the principles of motion and probability.

tribdog
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I just read about a new perpetual motion machine and it looks like it will work. You take a cat and tie a piece of toast on to its back. then you butter the toast and toss the cat into the air. Since the toast has to land butter side down and the cat always lands on its feet it spins forever.
 
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I don't think it would spin forever, because eventually the cat will die (:frown:) and dead cats don't have to land on their feet.
 
When the cat hits the ground the toast hasn't really landed. Thus once again confirming that the laws of physics do hold!
 
That theory about toast always landing butter side down is just a myth. The chances of landing butter side down depend on the ratio between table height and toast length.

For a standard 5" piece of toast, the chances of landing butter side down is only better than 50% if the table is between 12 inches high and 110 inches high (approximately). The chances are better than 90% between 30 inches high and 70 inches high.

If you use a larger piece of toast, say a 12" piece of toast, the chances of landing butter side down are better than 50% when the table height is between 30 inches high and, uh, really high. The chances of landing butter side down are better than 90% when the table height is between 75 inches high and 170 inches high.

And, naturally, that assumes a perfect landing surface that will absorb virtually all of the bounce. The worse the landing surface, the more likely you are to get a lucky bounce and have the bread land butter side up.
 
Would it help if the cat was tossed onto a trampoline??:biggrin:
 
http://uncyclopedia.org/wiki/Cat-Toast_Device
 
Focus said:
When the cat hits the ground the toast hasn't really landed. Thus once again confirming that the laws of physics do hold!

Well at least the laws of statistics are broken, given that the cat always hits the ground instead of butter. I think we have an infinite improbability drive here, not a perpetual motion machine.
 
humanino said:
http://uncyclopedia.org/wiki/Cat-Toast_Device

The link in that article details experimentation on toast droppings: http://cockeyed.com/science/toast/toast1.html. They're bad at math (2/20 is a 10% survival rate, not a 5% survival rate), but that might just be a side effect of sticking a knife in the toaster to free a stuck piece of toast. I don't think Brooke paid enough attention to making the sure the plate was always at the same angle, either. A better test would have been to slowly push the toast towards the edge of the table until its center of gravity was just beyond the table edge. I think that would have gotten more consistent results.

All in all, I'm not even sure they're scientists.
 
Last edited by a moderator:
I've never dropped a piece of toast off of a table. I don't even know how that's possible. I've only dropped it out of my hand either because it is too hot, in which case I haven't buttered it yet, or when I was in the process of buttering it.
 
  • #10
tribdog said:
I've never dropped a piece of toast off of a table. I don't even know how that's possible. I've only dropped it out of my hand either because it is too hot, in which case I haven't buttered it yet, or when I was in the process of buttering it.

Personally, I avoid those problems by buttering and spreading jam on the bread before inserting it into the toaster. It's a good toaster, too, except the side with the butter and jam tends to stick to the ceiling.
 
  • #11
There must be an exception to the rule here, if one is holding the toast and it breaks i sure 9 times out 10 it will fall butter side down.
 
  • #12
BobG said:
And, naturally, that assumes a perfect landing surface that will absorb virtually all of the bounce. The worse the landing surface, the more likely you are to get a lucky bounce and have the bread land butter side up.

It's the bounce that gives the buttered side the advantage. If the dry side hits first, you get a bounce to flip it to the buttered side. If the buttered side hits first, it'll stick to the floor and reduce the chances of bounce to negligible.
 
  • #13
Okay, I just tried to perform the experiment. Unfortunately, this cat rather likes the toast and won't cooperate as needed. Now she's in a temporary state of perpetual licking.
 
  • #14
OAQfirst said:
Okay, I just tried to perform the experiment. Unfortunately, this cat rather likes the toast and won't cooperate as needed. Now she's in a temporary state of perpetual licking.

Thank God for that, they forgot to mention that if the theory is true then the buttercat will turn into a black-hole.
 

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