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Attempting to create a self rotating magnetic bike

  1. Jul 16, 2013 #1
    Hi all, new on here so thanks in advance for your responce's

    I am an avid cyclist and competant engineer, i dislike oil and gas so much i do not own a car. I cycle everywhere.

    I am tired of wanting to go long distances without assistance or a high top speed.

    I want to build a cycle with the main acceleration and main maintained top speed controlled by magnetic force.

    Not a hybrid bike using household electricity thus using my power thus coming from the same consumable fossil fuels.

    does anyone out there have any links or point me in the right direction to where i can find information about what magnets to use, are there already cylindrical self maintaining rotating systems out there?
    i have many designs floating around from the simplist being magnets on the frame of the bike being fixed to linear bearings being able to move away from magnets fixed on the wheel.

    I am affraid that my simple designs will not give me a high top speed. I am thinking 100km. also i need good acceleration also, to enable me to have the same acceleration as any car on the road in a city environment and then obviously be able to travel at the speed limit.

    the bike will look as much as it can like your average road bike, two wheels, gears, double disc brakes or better, changing gears i think will still be needed for that initail push and perhaps for overtaking. i am whoever open to all ideas and thoughts.

    i hope you get what im trying to achieve here and once again thank you for your input and replies.


    Engineer Carlos NZ
     
  2. jcsd
  3. Jul 16, 2013 #2

    berkeman

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    Welcome to the PF.

    It sounds like you are asking about perpetual motion machines (PMMs). We do not discuss or debunk PMMs here on the PF.
     
  4. Jul 16, 2013 #3
    I'm afraid Carlos you been misled by your lack of knowledge and ofcourse mainly the internet.
    The universe and pretty much everything in it exists the way it is but in order for something to change there needs to be a force , work needs to be done , when you do work you use up energy , something transforms into something different like gasoline to mechanical energy+heat +wear etc.
    Magnets themselves don't do work , well they do until they find their matching poles then they stop, so you can get like 0,5 rpm with a magnet motor and then it stops.
    I guess the best choice will be to go with batteries and electricity.
     
  5. Jul 17, 2013 #4

    CWatters

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    What others have said. Magnets are not a primary energy source. You can't make a motor using only permanent magnets. That hasn't stopped numerous people trying to do so or even posting claims to have a "working" motor on youtube. All fake or misguided.
     
  6. Jul 17, 2013 #5

    CWatters

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    It took me a while to understand why but there is a similarity to gravity. Consider the potential energy gained by a climber is m*g*Δh. The dimension Δh does not depend on the route taken only the height difference between starting and finishing points. If the climber returns to the starting point then Δh=zero and no potential energy has been gained or lost by the climber.

    Much the same applies to magnet motors. If you build a rotating machine then by definition after one or more revolutions it returns to the same point where the magnetic equivalent of Δh above is zero. It also doesn't matter which route is taken (eg which way the "motor" rotates). The net energy gain is zero.

    At some point you will find people who claim this can be "solved" using magnetic "shields", but in effect they are just the equivalent of a climber taking a different route. If the climber/magnets ever returns to the starting point the net energy gain is zero.
     
  7. Jul 17, 2013 #6
    Good analogy CW:)
    The only way a magnet motor would work is if we could separate the poles , like have only S's or N's then it would work in the right angles as every magnet on a rotor would try to repel every magnet in the stator , but since this cannot be done , ehh well.We get every one pole trying to push away and every other trying to hold back , the net result is zero
     
  8. Jul 17, 2013 #7

    Dale

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    Even with monopoles it would still be conservative.
     
  9. Jul 17, 2013 #8

    CWatters

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    What Dale said. Monopoles don't help. The rotor of any magic machine would still have to return to a previous position eventually.
     
  10. Jul 17, 2013 #9

    berkeman

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    Since the OP has not responded, this thread is locked as a PMM debunking discussion.
     
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