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It's funny. Laugh. Science

The Museum of Unworkable Devices 309

Posted by timothy from the more-fun-than-broken-packets dept.
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."
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The Museum of Unworkable Devices More

The Museum of Unworkable Devices

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  • The newest item added to the exhibition... (Score:5, Funny)

    by netsharc ( 195805 ) on Saturday March 29, 2003 @06:31PM (#5623814)
    the server that hosted the site!

  • Also known as the (Score:3, Funny)

    by Tablizer ( 95088 ) on Saturday March 29, 2003 @06:31PM (#5623815) Journal
    MS-Windows Museum :-P

    (somebody had to say it)

  • Why didn't they just ask... (Score:3, Funny)

    by ksheka ( 189669 ) on Saturday March 29, 2003 @06:33PM (#5623825)
    ...Lisa Simpson?

  • Goody! Lots of ideas... (Score:5, Funny)

    by irritating environme ( 529534 ) on Saturday March 29, 2003 @06:34PM (#5623830)
    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.
    • "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."

      If you used "viral marketing" you won't just have perpetual motion...you will create energy from the ether as excitement around the idea grows. Physics meets MLM.

  • Scientists ? (Score:5, Insightful)

    by Anonymous Coward on Saturday March 29, 2003 @06:38PM (#5623846)
    > scientists have been getting it wrong ever since.

    No. NON-scientists have been getting it wrong.

  • A solution? (Score:2, Interesting)

    by Tweakmeister ( 638831 )
    It's just not possible. Energy will always be taken away in the process that can't be "recycled." It's neat to watch people try to make super efficient machines though...I wonder if any low friction fluids, etc. have come out through the development of these inventions?
    • take a box with gas and put the wall with the hole in the middle. Gas molecules will fly randomly in all directions. There is a chance (extremely low) that they will be gathered more in one half. There will be a pressure and if you will be lucky you can extract some energy from such pressure. In your dreams. In reality there is a second law of thermodynamics saying that enthropy cannot be dropped in the closed system.

      Now consider thousands of open source developers coding as one thousand monkeys typing on

    • People have made devices which can continually run, however I believe the definition of such a device requires that it creates energy. Adding energy by starting the device by hand isn't allowed, by starting a machine you are giving the machine energy which it can use to continue producing energy.

  • Unworkable-DRM. (Score:5, Funny)

    by Anonymous Coward on Saturday March 29, 2003 @06:41PM (#5623851)
    My nomination for the museum of unworkable devices is DRM

  • People will always try (Score:5, Insightful)

    by Blaine Hilton ( 626259 ) on Saturday March 29, 2003 @06:51PM (#5623876) Homepage
    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

    • Re:People will always try (Score:5, Insightful)

      by Space cowboy ( 13680 ) on Saturday March 29, 2003 @07:33PM (#5624015) Journal
      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.
      • Two people have replied to this thread with comments about how 98% efficiency is impractical with carnot heat engines. What about other engines? Electrical, gravity (hydro), or other solutions are all possible and can achieve MUCH higher efficiencies.

        On another point, if you lower the cold-sink of a carnot engine to almost absolute zero, you can achieve extremely high efficiencies, though again the practicality of this is dubious.

      • Re:People will always try (Score:4, Informative)

        by dhovis ( 303725 ) on Saturday March 29, 2003 @09:41PM (#5624359)

        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 [energy.gov] 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 [doe.gov] 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% [energy.gov]. That's because converting chemical energy => heat is not a Carnot limited process, and is only limited by the second law of thermodynamics.

      • large powerplants can get upwards of 75-80% thermal efficiency. The bigger the better. It always pays to buy in bulk ;)

        Of course, there's still an upper limit. But the fact that bigger engines/plants have always been more efficient is probably the #1 reason there isn't a mini powerplant in everyone's basement.

        Micro cogeneration only makes sense if you're tapping into energy that you're already producing but aren't using (or happen to be in a relatively remote location). IE: hot flue gasses off of your fur

      • Re:People will always try (Score:3, Interesting)

        by pla ( 258480 )
        I don't mean to argue with Carnot, but simple thought-experiment will demonstrate that you *can* do better, asymptotically aproaching 100%...

        Take a "perfect" Carnot-cycle engine. submerge it in a vat of water. The waste heat will warm the water, which you can then use to generate electrical energy clearly in excess of the Carnot limit.


        Additionally, the laws of thermodynamics have a serious flaw, which most folks who like to wag their finger and screech "The second! The second!" like so many autistic

    • The problem with your idea is thermodynamics (Score:5, Informative)

      by MyNameIsFred ( 543994 ) on Saturday March 29, 2003 @07:42PM (#5624039)
      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.

  • Buttered toast (Score:5, Funny)

    by TummyX ( 84871 ) on Saturday March 29, 2003 @06:51PM (#5623880)
    Where's the cat with buttered toast attached to its back?

  • problem with PM machines (Score:3, Interesting)

    by cyko500 ( 315074 ) on Saturday March 29, 2003 @06:53PM (#5623889)
    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.

    • Re:problem with PM machines (Score:5, Insightful)

      by Space cowboy ( 13680 ) on Saturday March 29, 2003 @07:46PM (#5624052) Journal
      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.

      • Re:problem with PM machines (Score:4, Insightful)

        by EngMedic ( 604629 ) on Sunday March 30, 2003 @01:19AM (#5624985) Homepage
        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.

  • Do they have the ultimate 20th-c vaporware? (Score:5, Funny)

    by saskboy ( 600063 ) on Saturday March 29, 2003 @06:53PM (#5623892) Homepage Journal
    Hydrogen Fuel Cells?

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

  • Well, there's your perpetual motion, right there. (Score:5, Funny)

    by blair1q ( 305137 ) on Saturday March 29, 2003 @06:57PM (#5623901) Journal
    The quest for perpetual motion has been going on since at least the 11th century

    Without ever stopping!

  • Poll: How many of us have tried? (Score:4, Interesting)

    by Neuronerd ( 594981 ) <konrad@ko[ ]ing.de ['erd' in gap]> on Saturday March 29, 2003 @06:58PM (#5623902) Homepage

    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?

    • "Why won't this work?" is a good way of learning all of the practical details of a system. "Why can't you put a wheel inside of a wheel inside of a wheel, and have them spin relative to the wheel just outside, and thus break the speed of light?" is a good one. Answer that, and you've just learned something. (Assuming just physics 101 knowledge.)
    • It was cool !! Metal wheels and magnets to pull itself along !! Never figured out how to stop it though.
    • In my 200-level physics class, I was constantly coming up with new "perpetual motion devices" for my teacher to shoot down. I understood full well that it was fundamentally impossible, but it's kind of nice to bash into your own preconceptions and watch them break.

      Anyways, the most interesting things I came up with weren't perpetual motion devices per se. I came up with some ideas that sucked energy from Brownian motion in matter. I don't think anything like that has ever been fielded as a large-scal

      • Well ... the the second law of thermodynamics seems to imply that even such micromachines are not possible because entropy would then be changed into the wrong direction.

        As said on lectureonline.cl.msu.edu: [msu.edu](You can browse through the book changing the url. "These machine then violate the second law of thermodynamics, as we will see in the following, and are thus impossible to work. This is much harder to see, because the concepts are rather delicate. The book proceeds to introduce the concept of Entropy"

      • There are cheats, some are more subtly than others.

        One that I've seen work was simply a bike wheel with thick black spokes (possibly dense rubber or plastic), no hidden batteries or anything.

        It only worked because of its position in the room, in particular its position relative to the window (the museum was closed at night-time, and we guessed it would stop at night, but could test this hypothesis (heck we were 10, we didn't even know it was called a hypothesis!)).

        To be precise, it only worked when it wa
    • I read a good book on this a long time ago, Tapping the ZPE by Moray B. King. The idea is that there are a set of circumstances that can cause a random system to move toward order. The work was based on the 1977 Nobel Prize winner in Chemistry, who discovered the circumstances that can cause that to happen. This was done without violating the second law of thermodynamics, and is probably why the guy got the Nobel Prize. I don't know his name.

      If I remember right, the circumstances were that the system had t
  • what of the timecube? [timecube.com]

    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.
    • I bestow upon myself the "Doctorate of Cubicism", for educators are ignorant of Nature's Harmonic Time Cube Principle and cannot bestow the prestigious honor of wisdom upon the wisest human ever.

      I'd have to say that's the best quote from that site.

      • [tongue in cheek]

        whether or not he deserves a "doctorate of cubicism" i think his real calling is in web page design, for which he deserves a "masters of hypertextism"

        the free form rant of size 7 fonts with alternating basic colors is... uh... stupendous

        [/tongue in cheek]
    • I was going to ask him to teach me the "Universal Secrets of the Time Cube" but then I read this:

      There is no teacher on Earth qualified to
      teach Nature's Harmonic Simultaneous 4-
      Day Rotating Time Cube Creation Principle,
      and therefore, there is no teacher on Earth
      worthy of being called a certified teacher.

      I guess I'm out of luck.

    • Wow....that page uses the words "dumb," "stupid" and "evil" more times than any document I've ever seen. Google [google.com] seems to agree with me.

  • Perpetual motion *IS* possible (Score:2, Insightful)

    by Anonymous Coward
    In a superconductor, electrical resistance is ZERO. Electric current will move forever.

    Of course, you need to keep your superconductor cold, so put it in outer space, or keep the liquid helium flowing.

    And for you nitpickers: yes, there are superconducters that work at liquid nitrogen temperatures, but you can't make wire out of them yet.
    • As long as there's a eletric potential difference. A superconductor dissipates zero energy when it is in transit. It does not feed that energy into itself nor generates energy.
    • So? If you spin a wheel in space, it'll rotate forever. Same concept, perpetual motion, but it isn't a machine because there is no energy conversion - part of the definition of a machine is (afaik) that it converts energy.
      • " So? If you spin a wheel in space, it'll rotate forever. Same concept, perpetual motion, but it isn't a machine because there is no energy conversion - part of the definition of a machine is (afaik) that it converts energy."

        Well not quit, now yes if you spin a wheel in space it will probably spin for a hella long time. But forever is no garentee, or even possible. Space is not perfect. It's not absolute zero and it's not a perfect vacuum. It runs slightly above abs zero and has plently of trace hydro

  • I've got it!!! (Score:5, Funny)

    by heli0 ( 659560 ) on Saturday March 29, 2003 @07:19PM (#5623974)
    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!!
  • Try using the Atari 5200 or Atari Jaguar joystick without taking your eyes off of the screen.

    I thouht I was terrible at Aliens vs. Predator until I realized I kept getting killed because I was staring at the controller more than I was looking at the game.

  • Voyager 10's on it's way to perpetual motion.... until it slams into something/someone.
    Matter 'o' factly, last I checked, it's getting faster.

    • Re:Go Forever? (Score:3, Informative)

      by Space cowboy ( 13680 )
      And until it slams into something, it's simply in perpetual motion, it's not a perpetual motion machine...

      A machine must do Work (definition: The transfer of energy from one physical system to another).

      Perpetual motion is easy. A perpetual motion machine is impossible.

      Simon.
      (Getting tired of pointing out that machines have to DO something)
    • " Voyager 10's on it's way to perpetual motion.... until it slams into something/someone.
      Matter 'o' factly, last I checked, it's getting faster."

      No it's speed limited. It's loosing energy to space, it gets tugs of gravity from everything in every direction, it's experiancing drag from trace hydrogen. For any given point in space there is a finite speed it can go due to achiving a force equalibrium with all around it (IE like your car when it can't go any faster since the forces against it == the force it

  • Excellent museum (Score:3, Funny)

    by quantaman ( 517394 ) on Saturday March 29, 2003 @07:25PM (#5623990)
    I mean even the server [netcraft.com] follows the spirit of the exhibits!
  • This reminded me of the Anime Laws of Physics [tarleton.edu].

  • Ha, just when you thought the field was closed, suddenly it's open again.... And since it's being exposed and marketed by Dr. Steven Greer you know it has to be true.

    The Transcript Here [disclosureproject.org]

  • I have a source of unlimited power (Score:5, Funny)

    by 91degrees ( 207121 ) on Saturday March 29, 2003 @07:29PM (#5624007) Journal
    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.

  • First hand experience (Score:5, Interesting)

    by gsyswerda ( 550684 ) on Saturday March 29, 2003 @07:29PM (#5624009)
    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.

  • almost (Score:5, Funny)

    by trb ( 8509 ) on Saturday March 29, 2003 @07:33PM (#5624014)
    I have a design for a perpetual motion machine that almost works.


  • Sorry, I've already solved it. Take two bodies, put them in a vacuum with no other external forces, and have them orbit each other without decay. There. Perpetual motion.
    • Sorry, I've already solved it. Take two bodies, put them in a vacuum with no other external forces, and have them orbit each other without decay. There. Perpetual motion.

      Maybe. If Einstein was right, the system will slowly lose energy by emitting gravitational radiation.
  • Isn't weather kind of a perpetual motion machine?

    I feel like (as a non-scientist, non-physicist) that I have an intuitive understanding that all self-contained devices relying only on their own mechanics would never attain perpetual motion due to the dragging forces of gravity, friction, and other forms of external resistance.

    But I don't have such an intuitive understanding that a machine that takes advantage of outside consistent forces as a source of energy (like gravity) could not attain perpetual motion. Especially if we loosen the definition of "outside consistent forces" from the scientific definition (those natural forces that always balance themselves) to the practical definition, like those forces that aren't naturally occuring but happen all the time anyway, like the directional airflow in a building's exit corridor, or the vibration of a dance floor, or all the other places in the world where energy is being expended and not captured. If we made machines that were built to rely on those forces always happening, and capturing them to convert them to energy, wouldn't that be generating more energy than is expended to run it, considering that the expended energy it depends on would be happening anyway? I know it's mathematically lazy but there's no reason why we can't double-count that stuff.

    • Isn't weather kind of a perpetual motion machine? In the sense that forever is as long as we live, then yes, it is. However, by definition a perpetual motion machine is one that keeps going without external energy. Ultimately, the wind moving around the globe and the clouds/rain/snow that go along with it all come from the heating energy of the sun, with the rotational force of the earth helping to direct some of the motion. Eventually, the earth will be subsumed within the boundary of the sun and the

    • Yes, no, and maybe. (Score:5, Informative)

      by freeweed ( 309734 ) on Saturday March 29, 2003 @09:07PM (#5624264)
      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 :)

    • nope (Score:2)

      by Xtifr ( 1323 )
      Isn't weather kind of a perpetual motion machine?

      No, the weather is driven by solar energy. When the sun runs down, weather stops. It's no more a perpetual motion machine than a battery-operated car is - it just has a "battery" that's going to last a good long time. :)
    • Most weather is due to the heat from the sun causing things like water evaporation and air currents due to warm air rising. If you put Earth out in the middle of space with no nearby star you would pretty much not have any weather.

  • Perpetual Motion Machines of the First Kind (Score:5, Interesting)

    by MillionthMonkey ( 240664 ) on Saturday March 29, 2003 @08:07PM (#5624129)
    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?

    • 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).
      • Its exactly like connecting an internal combustion engine up to a nearly infinite tank of gasoline.

        And don't forget, another nearly infinite tank of oxygen.

        If that were a correct analogy then perpetual motion machines of the second kind would be viable. There's nothing special about a machine that can run using a supply of gasoline and oxygen. But a machine that can extract useful work from a single heat reservoir of disordered ambient thermal energy would be nothing less than magic.

        This particular mach
        • IANAP (I Am Not A Physicist)...just a lowly architecture major, but I am assuming if an engine is relying on heat input as a sort of fuel, than a lack of heat differential would be problematic.
          • That's correct. There is only one heat reservoir.

            If this could work, we could have cars and airplanes that ran off the heat of the air surrounding them.

            Nobody ever spoke much of harnessing the power of the heat in the ocean, until those thermal gradients were discovered between surface waters and deep water. With two heat reservoirs you can transfer heat from one to the other, extracting some of the energy as a tax as it moves from warm to cold regions, generating nice things like fresh water and electric [slashdot.org]
      • That's not a perpetual motion machine of the first kind. That's just a motor with a really big fuel supply.

        A perpetual motion machine of the first kind is basically a machine that loses almost no energy because it has so little friction, air drag, resistance, etc. Because it loses energy so slowly, it can continue to move for a very long time. But because it's moving doesn't mean you can continously extract energy from it, as any attempt to extract energy will slow it down and eventually stop it. You w

    • 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?

      It's late on a Saturday night, I'm drunk, and I may be wrong, but haven't you just given it an external energy source ? What's the conceptual difference between that and a car engine with an everlasting supply of petrol ? I thought one of the requirements for a PPM is to not depend on external

      • It's late on a Saturday night, I'm drunk, and I may be wrong, but haven't you just given it an external energy source ? What's the conceptual difference between that and a car engine with an everlasting supply of petrol ? I thought one of the requirements for a PPM is to not depend on external energy sources.

        You've illustrated how these machines are better at fooling people (at least drunk Brits) than the simpler kind. PPMs of the first kind (like the ones on that web page) get scoffs from everybody becau
    • The planet itself becomes part of the PM machine thus nullifying the PM part as the planet will eventually cool and die.
    • >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.

      Hmm, some kind of Maxwell's demon. My intuition says that the transfered momentum per unit of time is the same for all particles, but I can't seem to prove it mathematically. The particles make circular trajector

      • Say a proton hits the propellor. It will bounce, move in a semicircle in toward the center, hit the propellor again, and keep bouncing in little semicircles until it almost reaches the propellor axis- then it will hit the other side of the next propellor vane- bouncing back up, away from the center, striking against the wrong side and pushing it the wrong way. So the propellor won't rotate at all and the machine doesn't work, for reasons that have nothing to do with the Second Law.

        In Feynman's The Characte
  • is the people in the movie The Matrix. What a crock! They somehow pump out more energy then they consume in "food" (nutrient solution or whatever). Perhaps it makes sense if you're taking one of those pills (what happens if you take red and blue at the same time?), but not in the real world.
    • you know, it's just entertainment. thats all. There not trying to get a Phd, there not an educational facility, they are movies.

      However, within the context of the movie, I would like to point out a few things.
      1)clearly they have modified the humans(you know, tubes and stuff), so who knows how there bodies function.
      2)The machines use to run soley on solar power. clearly far more advanced solar power then we currently have. After the humans blocked the sun, they adpted. perhaps by taking the radiens heat off
      • But it's so clearly drivel.. anyone who's gone through Physics II should know that. They could've come up with something better:

        1) Computers are based around biochips (and humans produce something they need), and humans are cheaper to make than custom bacteria.

        2) Parts of the human mind are used for processing. Biological minds are heavily tuned for certain tasks (image processing, perhaps?).

        3) Because the machines need human authorization/ activation to function (poorly implemented hardwired failsafe?)
    • AFAIK, the original script featured humans as a part of a supercomputer array, a Beowulf Cluster for a better Slashdot recognition. However, it was thought too difficult a concept for the ignorant masses, and the energy idea was used instead.

      Still, despite the problems with the Second Law, it could be possible that the Borg were using humans to _convert_ energy to a form more suitable for them. For example, to convert hydrocarbons into heat.

  • They think that perpetual motion is impossible, but I'm almost there!

    There's just one small problem with friction in the defrobnication rotor. All I need is some funding to fabricate a new one out of frictionless unobtainium, and then we'll see who's laughing!

    I'd be happy to demo the system to anyone willing to make a nominal million dollar investment. Second Law, make your time!

  • Magnets and PM (Score:3, Interesting)

    by mark-t ( 151149 ) <markt.nerdflat@com> on Saturday March 29, 2003 @08:51PM (#5624228) Journal
    I was quite surprised to not see a so-called PM device on this page which incorporated permanent magnets with the following explanation for why it cannot work:

    One cannot expect to use permanent magnetism as a source of perpetual motion because when a permenant magnet does work, it loses a certain amount of its magnetism in the process. This phenomenon can be seen directly with the following simple home-science experement: Place two magnets side by side, such that like poles are adjacent to eachother. Let go of one and note how far it gets pushed away. Now in a PM device, the magnets will obviously have to be brought back together at regular intervals -- so tape them together so that you effectively create an environment where the repulsion action is perpetual (which is what you are trying to achieve). Leave it alone for a few weeks. Come back after that time and remove the tape. Repeat the experiment that you did at the beginning and you will notice that the free magnet gets pushed quite a bit less than before -- sometimes not even at all! What is of particular interest is the stronger the magnets were originally, the more pronounced this loss of magnetism is, so powerful magnets quickly become weak magnets, which are capable of doing less work, and therefore require more time to lose a measurable amount of their magnetism.

    tanstaafl

  • Here's the Real problem... (Score:3, Insightful)

    by core plexus ( 599119 ) on Saturday March 29, 2003 @09:57PM (#5624396) Homepage
    "The trouble with most folks isn't so much their ignorance. It's know'n so many things that ain't so." -- A favorite quote of Richard A. Muller, by 19th century humorist Josh Billings.

    Weird News [xnewswire.com]

  • Comment removed based on user account deletion
  • In general, /. appears to be somewhat anti-patent biased.

    Regarding perpetual motion, however, the US has a strict patent policy. According to federal statute, 35 USC 101, perpetual motion machines are explicitly unpatentable as inoperative.

  • atoms (Score:3, Interesting)

    by Unregistered ( 584479 ) on Saturday March 29, 2003 @11:21PM (#5624654)
    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.

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