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Using centripetal force to fight lenz?

  1. Feb 8, 2010 #1
    hello to all, first post on this side of the web,

    maybe some of you folks can give me an opinion on something ive been running in my head

    ok, so this stemmed from thinking about how to overcome lenz law with gravity

    i thought of a magnet on the end of a lever, with a free standing inductor next to it, we push on the other side of the lever and this causes the magnet on the other end to pass the inductor and induce electricity

    the problem with this is that when we push down on the lever, the BEMF is directed downward

    lets interpret this as gravity, so in a sense it gets "heavier"

    this means to balance our lever we would need to add a counter weight and we could use less energy, however this presents a problem because on the upward stroke of the lever, the other side becomes "lighter"

    and now we have to lift the difference in weight of the lever, in addition to the force of the bemf

    then i thought about how it would behave on its side

    now, if we had a wheel or lever we were spinning, we would want it to be balanced, and currently it would be "unbalanced", because even if the weight ratios were correct, while it spun the magnet side would get "heavier" due to the bemf

    so i propose using the natural pull of centripetal force to allow a counterweight to gain distance from the axle, making the lever "balanced", could this possibly cancel out lenz law, if we use a flywheel?

    heres a quick drawing,

    let me know what you think

    Attached Files:

  2. jcsd
  3. Feb 8, 2010 #2
    No let's not.
    What natural pull of what centripetal force. The thing is only spinning because you apply a torque in the first place. You can then say that each part of the "lever" is acted on by a centripetal force but that does not constitute some untapped mystical source of energy.
  4. Feb 9, 2010 #3
    how clever of you to take a rhetorical question and answer it as if it were to be taken literally

    what i was talking about is lenz law suggests that a force is induced in the opposing direction of the magnetic field, in this case the opposite direction of the rotation of the lever

    a lever without a magnet is most efficiently spun when it is balanced, adding a counterweight adds a force on the other side of the lever, in the opposite direction of the bemf

    seeing as how bemf exponentially increases with rate of rotation, this implies we would need an exponential addition of energy on the other side to counteract this force and make the lever "balanced"

    the easiest way to make something heavier is to move it further from the axle, and instead of wasting energy with a motor to shift the weight, we could use the "natural pull" of centripetal force, seeing as how centripetal force is acting on the counterweight in a direction that goes away from the axle, outward, it would pull the weight to shift further away, on its own

    that is all i meant by it

    i never said my idea was factual or claimed it to be true, i just wanted to get an opinion on an idea i had

    i never suggested the movement of the counterweight away from the axle would yield magical energy, i do not no where you got this assumption
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