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  1. 04 Mar '08 12:04
    I guess lots of you have dreamt up ideas on this. Mine involved harnessing magnetic repulsion, a lightweight wheel with magnets attached would spin in a frame. As the wheel rotates the magnets attached to it get a small push via repulsion from a similar set of magnets attached to the frame, which are angled to that they only act in replusion. Perhaps the magnets would be electro magnetic, and could be switched. The idea could be applied to a train levitating on a magnetic repulsion track, to minimise energy loss by friction. In principle, if mass, friction and wind resistance were minimised it could work, what do people think?
  2. 04 Mar '08 13:56
    Originally posted by eamon o
    I guess lots of you have dreamt up ideas on this. Mine involved harnessing magnetic repulsion, a lightweight wheel with magnets attached would spin in a frame. As the wheel rotates the magnets attached to it get a small push via repulsion from a similar set of magnets attached to the frame, which are angled to that they only act in replusion. Perhaps the ...[text shortened]... iple, if mass, friction and wind resistance were minimised it could work, what do people think?
    Since perpetual motion violates fundamental laws of the universe, it wont work.
    The flaw in your idea is that it appears, from your description, that the magnets get pushed from one magnetic field to another, what you have ignored is the fact that at it enters the next magnetic field it will be slowed down again by the repulsion.

    Using magnets to levitate trains is an old idea and is actually in use on a few trains. It does help to significantly reduce friction, but it does not result in perpetual motion.

    I have a fun toy which includes a magnetic 'top' which you spin above a flat platform, and it floats about 2cm up in the air, and keeps going for quite a while until the air resistance slows it down. Its quite fun to watch.
  3. 04 Mar '08 14:13
    Originally posted by twhitehead
    Since perpetual motion violates fundamental laws of the universe, it wont work.
    The flaw in your idea is that it appears, from your description, that the magnets get pushed from one magnetic field to another, what you have ignored is the fact that at it enters the next magnetic field it will be slowed down again by the repulsion.

    Using magnets to levi ...[text shortened]... keeps going for quite a while until the air resistance slows it down. Its quite fun to watch.
    Perpetual motion violated fundamentals laws of classical physics. I think it's conceptually possible to create a perpetual motion experiment with current laws. Why? Zero field energy is not zero!
  4. 04 Mar '08 14:37
    Originally posted by twhitehead
    Since perpetual motion violates fundamental laws of the universe, it wont work.
    The flaw in your idea is that it appears, from your description, that the magnets get pushed from one magnetic field to another, what you have ignored is the fact that at it enters the next magnetic field it will be slowed down again by the repulsion.

    Using magnets to levi ...[text shortened]... keeps going for quite a while until the air resistance slows it down. Its quite fun to watch.
    to avoid the slowing down problem you describe, i thought that a shield of some sort miht work, or as i said the magnets get switched electrically. even if it wouldnt work perpetually, it might be possible to develop it as a form of power assistance?
  5. 04 Mar '08 14:40
    And there are superconductors with the same electrical current going on for years. No dissipation has been noticed yet. Almost perpetual... I think that's the best we made so far.
  6. Subscriber AThousandYoung
    Do ya think?
    04 Mar '08 15:11
    Originally posted by eamon o
    I guess lots of you have dreamt up ideas on this. Mine involved harnessing magnetic repulsion, a lightweight wheel with magnets attached would spin in a frame. As the wheel rotates the magnets attached to it get a small push via repulsion from a similar set of magnets attached to the frame, which are angled to that they only act in replusion. Perhaps the ...[text shortened]... iple, if mass, friction and wind resistance were minimised it could work, what do people think?
    Electromagnets are not consistent with the idea of PERPETUAL motion because you need to keep supplying them with energy.
  7. 04 Mar '08 22:30
    Originally posted by eamon o
    I guess lots of you have dreamt up ideas on this. Mine involved harnessing magnetic repulsion, a lightweight wheel with magnets attached would spin in a frame. As the wheel rotates the magnets attached to it get a small push via repulsion from a similar set of magnets attached to the frame, which are angled to that they only act in replusion. Perhaps the ...[text shortened]... iple, if mass, friction and wind resistance were minimised it could work, what do people think?
    If you could find a material that completely blocked the magnet flux of the approaching magnets then you would have solved one problem, as one poster already mentioned.
  8. 05 Mar '08 08:12
    Originally posted by eamon o
    to avoid the slowing down problem you describe, i thought that a shield of some sort miht work, or as i said the magnets get switched electrically. even if it wouldnt work perpetually, it might be possible to develop it as a form of power assistance?
    You have just invented the electric motor. The reason why it is not a perpetual motion machine, is because switching on and off an electro magnet uses energy. In fact, as it generates heat as well as motion, it uses more energy than the resulting motion which is why electric motors are not 100% efficient.
  9. 05 Mar '08 08:16
    Originally posted by serigado
    And there are superconductors with the same electrical current going on for years. No dissipation has been noticed yet. Almost perpetual... I think that's the best we made so far.
    If we are talking about perpetual motion where little or no energy is lost, then there are many examples. The spinning of planets for example or the motion of the earth around the sun, both loose energy at such a slow rate that it both will keep going for a very long time. However they are not quite perpetual, and in-fact the slowing down of the earths spin is measurable.

    However the initial poster was, I believe, hoping to create a energy producing machine.
  10. 05 Mar '08 14:06
    Originally posted by twhitehead
    If we are talking about perpetual motion where little or no energy is lost, then there are many examples. The spinning of planets for example or the motion of the earth around the sun, both loose energy at such a slow rate that it both will keep going for a very long time. However they are not quite perpetual, and in-fact the slowing down of the earths sp ...[text shortened]... able.

    However the initial poster was, I believe, hoping to create a energy producing machine.
    yes AND no, you see i think it would also be great to find some kink of power assistance for use on things like bicycles
  11. 05 Mar '08 17:31
    Originally posted by eamon o
    I guess lots of you have dreamt up ideas on this. Mine involved harnessing magnetic repulsion, a lightweight wheel with magnets attached would spin in a frame. As the wheel rotates the magnets attached to it get a small push via repulsion from a similar set of magnets attached to the frame, which are angled to that they only act in replusion. Perhaps the ...[text shortened]... iple, if mass, friction and wind resistance were minimised it could work, what do people think?
    I have seen videos of very simple setups like what you describe on youtube. Just search for magnet motors.
  12. 21 Mar '08 15:57
    Originally posted by dryhump
    I have seen videos of very simple setups like what you describe on youtube. Just search for magnet motors.
    yes that was the sort of thing i had in mind, but never actually built a model. are you suggesting that it doesnt work and is juct a trick?
  13. Standard member agryson
    AGW Hitman
    29 Mar '08 17:55
    Originally posted by eamon o
    yes that was the sort of thing i had in mind, but never actually built a model. are you suggesting that it doesnt work and is juct a trick?
    Well, my understanding is that a perpetual motion machine needs to give out more energy than it needs to keep going, hence the breaking laws of thermodynamics. As for a machine that simply goes on forever without a requirement for an excess of enrgy being generated, no need for superconductors or any such stuff, there's bound to be a certain percentage of hydrogen atoms that will always have the one bound electron.
  14. 29 Mar '08 18:33
    If the laws of thermodynamics isn't foolproof, and it can't be if a perpetum movile is possible, then it has a very profound impact of how universe itself is working.
  15. Standard member PBE6
    Bananarama
    31 Mar '08 13:52
    Originally posted by agryson
    Well, my understanding is that a perpetual motion machine needs to give out more energy than it needs to keep going, hence the breaking laws of thermodynamics. As for a machine that simply goes on forever without a requirement for an excess of enrgy being generated, no need for superconductors or any such stuff, there's bound to be a certain percentage of hydrogen atoms that will always have the one bound electron.
    Perpetual motion machines don't necessarily have to produce any energy, they just have to function without reducing the entropy of the universe as a whole. But it's funny that you mention the orbit of an electron around a nucleus, because the problem of why the electron doesn't spiral into the nucleus was a bit of a headscratcher in light of the second law. Outside-the-box consideration of this problem helped give rise to quantum mechanics.