Give use your best perpetual motion device ideas

In summary, the conversation discusses the concept of perpetual motion and the use of photons as a potential perpetual motion machine. However, it is argued that photons cannot truly be considered a perpetual machine as they are massless and require work to change their energy. The conversation also delves into the question of whether photons have gravitational mass, and how they exist in different forms depending on their frequency. The possibility of a thermal magnetic driver as a perpetual motion machine is also mentioned, but it is ultimately deemed as not truly fulfilling the criteria. Finally, the conversation concludes with a discussion on the nature of creation and invention.
  • #36
I don't know if there is a strict definition of "Perpetual Motion Machine". People who look back over the history of the attempts to make one have come up with classifications of them, from what I understand.

It seems to me that to qualify, a thing would have to be a man made device, as opposed to something that already exists in nature. And it would have to both require no fuel imput and be capable of producing useful work.

I think that gravity and magnets are perfectly acceptable, and even desirable, since so many perpetual motion machines have been attempts to get work by kind of tricking these forces into being unbalanced or intermittant.
 
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  • #37
so you couldn't just have this thing that moves forever; you have to be able to tap energy out of it? what would determine it as useful?
what if you have a device that's so perfectly designed that when you apply something to use the energy its producing it stops working correctly?
 
  • #38
yeh, if you can get something to work using gravity, magnetism, or buoyancy then you're golden.

the problem is, getting something that emits a constant force to DO something is always a one way ticket, so to speak :|

good luck, guys
 
  • #39
well if you can get something to perpetually motion here on Earth that's a start.

since there is no "frictionless" here, you must be getting SOME energy out of it to keep it moving.

you don't even have to try and "tap" the energy out of it, just accomplish that first step, preferably on something larger than a molecular level ;D
 
  • #40
bouncy: ingenious. this should be a fun thought to toy around with during the summer (perhaps longer). keep posting ideas and further definitions of a perpetual motion device.

can the movement be erratic or does it have to be stable and reliable?
 
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  • #41
relativelyslow said:
so you couldn't just have this thing that moves forever; you have to be able to tap energy out of it? what would determine it as useful?
It does usefull work if it supplies power to something we need power for. That could be anything from grinding grain into flour, to providing the electricity to run your computer. The out put of energy could be in just about any form.
what if you have a device that's so perfectly designed that when you apply something to use the energy its producing it stops working correctly?
I wouldn't call that a "perfectly designed" device. The word "delicate" would be better.

The Crookes Radiometer is something like this. It spins continuously if there is enough ambient thermal energy, but that is all it can do. The difference between it running or not running is so fine that any attempt to harvest any enrgy from it would stop it dead in most cases. It is delicately balanced at the edge of the amount of friction it can overcome. There's just the tiniest, tiniest little bit of excess energy left. Not really worth going after.

If you could design a devise like that which ran off of gravity, or the field of a stationary permanent magnet, people would be completely astonished, of course, but you wouldn't get any work out of it.

Some people are going for the astonishing defying-the-laws-of-physics effect, and other for the work-out-with-no-fuel-in approach.
 
  • #42
relativelyslow said:
can the movement be erratic or does it have to be stable and reliable?
I have never heard of one you could call "erratic" but I don't suppose it makes a difference.

Thing is: look into the ones that have already been tried. No point in reinventing the broken wheel.
 
  • #43
well, I've seen this video of a frog hovering over a magnet (they did it with a water droplet too and various other things). I am assuming it would continue to do so without fail but the movement will not be predictable. it just floats around, twisting and turning. its kinda funny. should i just search online for previous attempts?
 
  • #44
http://www.hfml.sci.kun.nl/levitation-movies.html there's the link to the site with the floating things.
 
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  • #45
Is a planet orbiting in a perfect non decaying orbit around a black hole a perpetual motion machine? Or perhaps an electron orbiting an proton in a vacuum a perpetual motion machine? (End of the universe defining the limits on perpetual if there is such a thing.)
 
  • #46
relativelyslow said:
should i just search online for previous attempts?
This site has examples of all the commonly tried ideas:

The Museum of Unworkable Devices
Address:http://www.lhup.edu/~dsimanek/museum/unwork.htm
 
  • #47
mee said:
Is a planet orbiting in a perfect non decaying orbit around a black hole a perpetual motion machine? Or perhaps an electron orbiting an proton in a vacuum a perpetual motion machine? (End of the universe defining the limits on perpetual if there is such a thing.)
"Perpetual motion" has traditionally been applied only to devices invented by people (on paper or in their head) that need no fuel imput and from which you can get usefull work. It isn't a perfectly accurate thing to call them. Alot of people, therefore, bring up the subject of natural phenomena that, as far as we know, will keep on going till the universe ends, and present these as "perpetual motion".

This is a kind of game, I suppose, trying to prove the statement "There's no such thing as perpetual motion," wrong. It is based on a literal interpretation of "perpetual motion" rather than the unworkable machines it the term was first coined to describe.

The fact remains that whenever anyone has made a physical embodyment of one of these machines they don't work. It is instructive to examine them, though, and figure out why they don't do what the inventor expected them to do.
 

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