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Magnetism Another Element to Manipulate?

  1. Oct 4, 2008 #1
    I was wondering if we can use magnets to spin items in a way that they will continuously spin for a very long time with good conditions of the material used. By this I mean it can spin for a very long time without being touched or relying on any other thing to help it spin. other then the pull of its own magnet material. i think if all was taken seriously and measured, balanced and made almost perfectly even on all sides it should work. and if it does we could use this to generate electricity right? doesnt something have to spin in order to create electricity and if we could we want something to spin itself by itself for atleast a very long time? and if we could get something to spin like that the faster i would go the more electricity will be generated right? i am almost positive if we use magnets like this it could be very easy to get it to spin how fast and how long we want it to spin based on how many magnets are used and how powerful they are are aslong as they are not actually touching themselves right? this is a picture of my initial idea but even if this doesnt sound logical but the concept seems any way plausible I would like for anyone to give a better idea on how this could work best.

    i noticed with magnets theres always one point that pulls to it and the opposite of that point pushes form it. so I have 2 ideas that might work in both ways. 1 using magnetic pull to move things and 2 using magnetic push to move things. heres a picture of what i mean in the first idea:

    remember: this is just a reference idea it should have to be very even and well measured and balanced in order to get the best results... if anyone wants to do an experiment with this please do so becuase i lack the knowledge and tools to make and balance and measure such a project but all you really need side from that is 4 good magnets and some wood to create the wheel and axel and limbs for the magnets to be put on the limbs and spin the wheel on the axel. if it doesnt work with the wheel being right side up try it in diffrent positions but make sure its always evenly balanced.

    and also remember that im not certainly positive this will work the only thing i am almost positive of and just almost becuase i cant move my hand fast enough like that that if i try to connect 2 magnets to eachother hold one and having the other just lay still and if i put the one im holding close enough for the other to react and then beable to jerk away my hand fast enough for it not to gain contact but not so fast that it will loose contact and if i could get my hand to move like that forever the other magnet should follow forever you know what i mean right?

    also sorry for the walls of text i have a hard time explaining things becuase of my poor education. and i also apologize for incorrect grammer and spelling ect. but i think you should beable to understand me well enough. if not please ask me to explain.

    ok heres the picture of the first idea: ill make the picture of the 2nd idea later...

    the picture is in the attachment i dont see a add picture from url feauture thing sorry again... please tell me if this at all sounds plausible and if anyone wants to help me do this experiment thanks! and if by any means anyone else thought of this before me please go ahead and say.

    Attached Files:

    • i.bmp
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  2. jcsd
  3. Oct 5, 2008 #2


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    Maybe I am missing something, but I think you are describing magnetic bearings. They have been around for a very long time and are used in e.g. certain types of pumps.
    Anyway, magnet bearing are nice because of the low friction at high speeds. If you want really good performance you can even use superconducting bearings.

    That said, I think you are missing an important point: If you connect the axis of a spinning wheel to a generator that will ALWAYS slow the wheel down because energy is used to turn the generator.
    There is no free energy, when a generator is used to generate electricity this way you are really just converting kinetic energy to electrical energy so eventually the wheel will stop rotating(this is why superconducting flywheel can actually be used as "batteries").

    The energy losses due to friction in the bearings are generally insignificant, which means that in most situations it doesn't matter if you are using magnetic bearings or e.g. ball bearings.
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