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The Museum of Unworkable Devices

Jippy_ writes "The quest for perpetual motion has been going on since at least the 11th century according to this site, and scientists have been getting it wrong ever since. Take a gander at some of the most valiant efforts (and ultimately the biggest failures) in trying to beat the laws of physics through the last 1000 years, along with other impossible inventions and devices."

28 of 306 comments (clear)

  1. The newest item added to the exhibition... by netsharc · · Score: 4, Funny

    the server that hosted the site!

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  2. Also known as the by Tablizer · · Score: 3, Funny

    MS-Windows Museum :-P

    (somebody had to say it)

  3. Goody! Lots of ideas... by irritating+environme · · Score: 5, Funny

    For new bogus-physics product companies to get coverage from wired.com and get 10 million in funding

    I think that the problem with these devices isn't the laws of physics per se, I think its just that they were never properly marketed.

    --


    Hey, I'm just your average shit and piss factory.
  4. Re:Why didn't they just ask... by Anonymous Coward · · Score: 5, Funny

    In this house we obey the laws of Thermodynamics!

  5. Scientists ? by Anonymous Coward · · Score: 5, Insightful

    > scientists have been getting it wrong ever since.

    No. NON-scientists have been getting it wrong.

  6. Unworkable-DRM. by Anonymous Coward · · Score: 5, Funny

    My nomination for the museum of unworkable devices is DRM

  7. People will always try by Blaine+Hilton · · Score: 4, Insightful

    I for one have always been interested in perpertal motion machines and the related laws of physics. I believe so that if we could just improve effeciency we will achieve very near pertual machine like effects. I meen if we are using engines that are only 40% effiencent and we can improve that to 98% then that is still very possible. IMHO

    1. Re:People will always try by Space+cowboy · · Score: 5, Insightful

      I wonder which way (physics or perpetual motion) your interest swings. The Carnot cycle places a limit on even ideal circumstances for the thermodynamic production of Work from Energy.

      For a typical steam power plant, (800K hot, 300K cold), the maximum theoretically possible efficiency is ~60% for a 100% reversible reaction (hint: these don't exist in power plants). I seriously doubt it is possible get anywhere near 98% efficient without some new ground-breaking physics in the same vein as Newton -> Einstein.

      Simon.

      --
      Physicists get Hadrons!
    2. Re:People will always try by dhovis · · Score: 3, Informative

      Actually the Carnot cycle puts a limit on the conversion of heat energy into any other form of energy (kinetic, potential, electrical, magnetic, chemical, nuclear, etc). However, heat is the only form of energy so limited. Other conversions, say chemical => electrical are only limited by the second law of thermodynamics. For that matter, converting any other energy to heat can be very efficient. Electrical energy => heat, for example.

      So, something like a microturbine is limited to ~30% efficiency for electricity generation. Larger plants can get up to 35% efficiency. A fuel cell has no such limit and could potentially reach into the 90% range for efficiency of electricity generation. Hybrid fuel cell-turbine generation systems are being tested which have efficiencies of over 50% and they speculate that they could hit 70% or more. The problem with such a system is that the upfront cost is very high and it does not get offset by the savings in fuel. Not yet, anyway.

      Remember too that conversion of any energy to heat can be very efficient. Natural gas furnaces can be extremely efficient, as high as 97%. That's because converting chemical energy => heat is not a Carnot limited process, and is only limited by the second law of thermodynamics.

      --

      --
      The internet is the greatest source of biased information in the history of mankind.

  8. Buttered toast by TummyX · · Score: 4, Funny

    Where's the cat with buttered toast attached to its back?

    1. Re:Buttered toast by macemoneta · · Score: 4, Funny

      I thought that was an anti-gravity device? At least that's what I've been using mine for.

      --

      Can You Say Linux? I Knew That You Could.

  9. problem with PM machines by cyko500 · · Score: 3, Interesting

    In theory a PM machine CAN work. Only one itty bitty problem... The machine needs to be perfectly designed and built. Also, no mass can be gained or lost (A perpetual waterfall can't work because water evaporates). PE(potential energy)=KE(kinetic energy) so you use the KE to make more PE. The major problem comes in when someone wants to use this machine to power somthing. Then some of that KE is used for other work than "recharging"(adding PE back to) whatever medium you are using to power your PM machine. This causes the machine to slowly lose its energy and come to a halt. There must also be no interferance at all (no wind, rain, or movement of the machine). Gravity and atmosphere wouldn't cause the machine to stop though. Again... it is possible to make on of these machines but: a) It must be designed and built flawlessly and b) It cannot be used to power anything other than its own movement.

    1. Re:problem with PM machines by Space+cowboy · · Score: 4, Insightful

      You're defining a PM machine by excluding the 'machine' bit. Part of the definition of a machine is that it has to do Work (technical definition - The transfer of energy from one physical system to another).

      A body set spinning on a (somewhat miraculous) journey along an isopotential of gravitational force in the universe will continue spinning for eternity (or thereabouts. The universe might collapse...)

      The spinning body's still not a perpertual motion machine because it doesn't interact, and should it ever interact, it'll be subject to the laws of motion and thermodynamics and still not be a perpetual motion machine.

      Simon.

      --
      Physicists get Hadrons!
    2. Re:problem with PM machines by EngMedic · · Score: 3, Insightful

      physics is a very terse discipline - most words have only one meaning. to be completely technical, Work is one of several things : the dot product of Force and Distance vectors, or the integration of Force with respect to distance. Defining it as the transfer of energy isn't wrong, per se... but it's definetly hazy, and that kind of sloppy definition has a nasty habit of leading to trouble.

      --
      filter: +3. Hey, look! all the trolls went away!
  10. Do they have the ultimate 20th-c vaporware? by saskboy · · Score: 4, Funny

    Hydrogen Fuel Cells?

    Surely they must be there, at least for another 10 years ;-)

    --
    Saskboy's blog is good. 9 out of 10 dentists agree.
  11. Well, there's your perpetual motion, right there. by blair1q · · Score: 5, Funny

    The quest for perpetual motion has been going on since at least the 11th century

    Without ever stopping!

  12. Poll: How many of us have tried? by Neuronerd · · Score: 3, Interesting

    I am a scientist now and after studying physics I guess I am completely cured from the idea that there could be a perpetuum mobile, a machine that produces energy out of vacuum.

    But I remember say 20 years ago I spent a long time trying to invent such machines. I kept trying to design it and kept asking people why it wouldnt work. It took a long (frustrating) time before I could sortof acknowledge that it didnt seem to work.

    So honestly... who has undergone the same process?

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  13. and the timecube? by circletimessquare · · Score: 4, Funny

    what of the timecube?

    I have requested that the UCS, or
    Union of Concerned Scientists, act
    to evaluate Nature's Harmonic Time
    Cube Principle of Creation - for the
    welfare of children, nature and the
    future of all humanity. The dumb,
    stupid and evil bastards have ignored
    their obligation to their humanity
    fellowship to research Time Cube,
    and deserve to be spit upon publicly.
    It is their moral duty to test Time
    Cube, and a curse of evil if they ignore
    the greatest discovery of humanity.
    I have offered $10,000.00 to the evil
    bastards if they disprove Time Cube.
    They can't disprove it, so they hide
    like yellow-belly bastards they are.

    --
    intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
  14. I've got it!!! by heli0 · · Score: 4, Funny

    A flawless design for a perpetual motion machine... the only thing I need to make it work are a couple monopole magnets and a room-temperature superconductor. Honest!

    Send $1,000 to P.O. box 324, NY, NY 20002 to get in on the ground floor!!

    --
    Whenever the offence inspires less horror than the punishment, the rigour of penal law is obliged to give way...
    1. Re:I've got it!!! by neurostar · · Score: 4, Funny

      Send $1,000 to P.O. box 324, NY, NY 20002 to get in on the ground floor!!

      I'm guessing that with the intelligence of some of the /. crowd, you should be recieving approximately $20,000 in unmarked bills within the next week...

      ;)

      neurostar
  15. I have a source of unlimited power by 91degrees · · Score: 5, Funny

    The Troll Engine.

    what it does is post a comment extoling the virtues of Windows 95 over Linux. It then uses the heat generated by the ensuing flamewar to power a small town.

  16. First hand experience by gsyswerda · · Score: 5, Interesting

    When I was younger, in early high school, I discovered that my father was trying to build a perpetual motion machine in his basement workshop. It was a rotating wheel with slots that contained ball bearings. The idea was that the bearings would roll in the slots in such a way that the wheel would constantly be unbalanced, causing it to rotate forever. He hadn't quite gotten it to work, of course, and was concerned about the angle of the slots and friction at the hub. I had taken some physics by then, and tried to explain to my dad about conservation of energy and how his machine, in principle, could never work. Maybe he was already discouraged by then, but he quit working on it shortly after that.

    --
    Make a difference: move to a swing state.
  17. almost by trb · · Score: 4, Funny

    I have a design for a perpetual motion machine that almost works.

  18. The problem with your idea is thermodynamics by MyNameIsFred · · Score: 4, Informative

    The problem with your idea is thermodynamics. Thermodynamic analysis will tell you the maximum efficiency that an engine can acheive. Look up the Carnot engine (or cycle) for a good discussion. A Carnot engine is the most efficient engine possible, nonetheless, the thermodynamic limits are a killer. Throw in friction, realistic melting points for materials, etc. and the world is a dreary place. Engines will NEVER approach 98% efficiency.

  19. Perpetual Motion Machines of the First Kind by MillionthMonkey · · Score: 4, Interesting

    I got the page to load before it got slashdotted, and it looks like these are all perpetual motion machines of the first kind. These machines violate conservation of energy.

    Perpetual motion machines of the second kind don't violate conservation of energy, but they rely on a decrease in entropy. With a machine like that a ship could run an engine that extracts energy from the ambient water temperature to do work, leaving a trail of colder seawater behind the ship. That doesn't violate conservation of energy, but it does cause a global reduction of entropy.

    It takes more cleverness to come up with a machine of the second kind, and it's usually less obvious why they don't work.

    Here's a machine like that. Assume we have a propellor made of some heat resistant material like ceramic, inside a larger ceramic housing in which it is free to rotate. Stick a big permanent magnet around it so that there is a magnetic field running through it, parallel to the propellor axis. Now inject a hot plasma of some sort into the device. Electrons in the plasma move in tight little counterclockwise circles because of the field. Protons move in much wider clockwise circles (they're heavier), so they hit the propellor blades preferentially in one direction and make it rotate.

    Of course the plasma is going to cool down quickly if the protons in it are imparting kinetic energy to the propellor. So as a perpetual motion machine of the first kind, it's obviously going to run down and stop. But take the whole machine and drop it on a planet where the ambient temperature is high enough to keep the plasma hot. As the propellor extracts energy, more heat flows into the machine. What's wrong with it now?

    1. Re:Perpetual Motion Machines of the First Kind by Dynedain · · Score: 4, Informative

      Its exactly like connecting an internal combustion engine up to a nearly infinite tank of gasoline. Its not a perpetual motion machine, it simply has a fuel source that is seemingly infinite (in this case, heat).

      --
      I'm out of my mind right now, but feel free to leave a message.....
  20. Yes, no, and maybe. by freeweed · · Score: 4, Informative

    You're sort of mixing up what you're talking about, but mostly, you're on track. It's trivially easy to cause something to obtain perpetual motion - as many other posts have pointed out, just toss something into space. Odds are it'll keep going forever. Perpetual motion isn't hard at all (after all, Newton's laws effectively demand that it be possible). A perpetual motion MACHINE, on the other hand...

    As for weather, the problem is you're relying on an external power source - the sun. Turn that off, and boom, no weather (well, eventually anyway). You are correct though, we can use this energy that's just sitting around and gain more than we put into something. In fact, this is how our entire planet survives - both its organisms and our modern society. Think hydroelectric damns and wind turbines - they're just using something that's there anyway. And plants take advantage of the ever-present sun to store chemical energy within themselves, which other organisms then use when they eat said plants, etc.

    The problem still lies in self-contained systems. A friend of mine took years to believe me that you couldn't run a ship (assuming no wind outside) with windmills powering a motor that actually powers the ship. Friction is a bitch :)

    --
    Endless arguments over trivial contradictions in books written by ignorant savages to explain thunder in the dark.
  21. atoms by Unregistered · · Score: 3, Interesting

    atoms seem to be stable. electrons are moving. Isn't this perpetual motion? I know it's not the same but i've never heard a good reason why.