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A perpetual machine model that sets me thinking

  1. Mar 12, 2012 #1
    Now I'm not a PMI (perpetual machine inventor). In fact I'm quite convinced that there is no such thing as that. But a while ago, I saw the schematics of a perpetual machine that is hard to debate.

    Well this is how the machine worked. The inventor argued that if you have two magnets as arranged in figure A, with a ferromagnetic substance in between, the magnets will be attracted toward the metal. But as you bring the objects upwards, they'll repel each other as the metal gets thinner and the end is reached.

    Now based on this argument, he created an arrangement as shown in B and argues that these wheels would rotate forever, as the magnet's attract at the bottom of the metal piece and repel towards the top.


    Now this looks very convincing. Can anyone resolve this???
  2. jcsd
  3. Mar 12, 2012 #2
    And also, do tell me how to rotate an image by 45 degrees in Windows 7 Paint, if you know.
  4. Mar 12, 2012 #3


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    E N E R G Y

    is always why it won't work. It always is.

    Forget the forces that you think you can see operating. To get the wheel from that position to the next, you need to put energy IN. The wheel will reach an angle where the Potential energy is at a minimum and it will stay there (or oscillate about the position, finally coming to a halt).

    Windows Paint sucks. Get a decent free drawing package like Open Office and that will do all the simple (vector) drawing you need. Much better.
  5. Mar 12, 2012 #4


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    Staff: Mentor

    We do not waste people's time discussing PMMs here on the PF. That is why it is on the Banned Topics list at the Rules link at the top of the page. Please read some of the old locked PMM threads to find out why they don't/can't work.

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