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How can I control the magnetic field?

  1. May 16, 2007 #1

    Ped

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    Hi, I need help. How can I redirect/bend magnetic fields such that it will go in one direction instead of all around. That is going in a straight path instead of into multiple directions. :smile:
     
  2. jcsd
  3. May 16, 2007 #2

    ZapperZ

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    Sit inside a long, large solenoid.

    Zz.
     
  4. May 16, 2007 #3
    Or beside an infinite plane of current...
     
  5. May 16, 2007 #4
    use a network of quantum dots aligned and configured as 3-toroidal lattice to modulate the local e-m field through the donut-hole like a nozzle- q-dots can be configured into vast numbers of 'virtual elements' since they do not have a nucleus with neutrons limiting them to only the 92 stable atoms in nature- so any number of superconducting properties could be harnessed to allow the q-dot network to provide coherent e-m through most of the energy spectrum- I will let you work out the engineering hurdles
     
    Last edited: May 16, 2007
  6. May 16, 2007 #5
    u mean u want to be like magneto?
     
  7. May 16, 2007 #6

    Ped

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    thanks! Is there another way where I can do that? How about using an opposing magnetic field to redirect another magnetic field?
     
  8. May 16, 2007 #7

    Ped

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    zapperz : that might not be comfortable..haha

    neodevin : do you mean that using an infinite plane of current you could bend/rediriect magnetic fields?

    pakmingki: haha, not really, but maybe something like it..:biggrin:

    setAI: sounds like it will take me years working on that..but thanks!
    Is there any other alternative besides using quantum dots?
     
  9. May 16, 2007 #8

    ZapperZ

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    I didn't realize that comfort is part of your physics requirement.

    Zz.
     
  10. May 16, 2007 #9

    Ped

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    ZZ: Its not. But I don't think I could fit inside a long large solenoid anyway. But seriously, do you know of some method or theoretical idea that could redirect magnetic fields without using quantum dots?
     
  11. May 16, 2007 #10
    Then it isn't large enough. If comfort is an issue, build a sofa in it. Or a house. Problem solved :biggrin:
     
  12. May 16, 2007 #11
    I don't think you understand how magnetic fields act. Magnetic fields add. The long solenoid and infinite current sheet are both systems that produce a nice, straight magnetic field (which was what you initially sounded like you were asking for). They do that because, when you add together all the fields due to all the individual "pieces" of current, the sum is a nice, straight field.

    I don't know what you mean by "redirecting" or "bending" magnetic field. It's not like magnetism is some long straight "ray" that goes in one direction unless it's "bent". Magnetic fields could sort of be said to "tend to point in circles" I guess. Can you be more specific about the field you want to achieve?

    If you are trying to "conduct" a magnetic field across a distance without losing too much strength, there are several ways to do it. The main way is just to use a bar made out of a ferromagnetic material like iron.

    Yeah, I'm pretty sure he was kidding.
     
  13. May 17, 2007 #12

    berkeman

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    Um, if this question were posted in the EE forum, it would have been answered very quickly and accurately. Should I move it? :rolleyes:

    Quiz Questions -- what is the difference between netic and conetic materials? Why would you use both in concert to redirect magnetic fields?
     
  14. May 17, 2007 #13

    Ped

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    berkeman: that would be great, thanks :smile:

    Xezlec: thanks for the ideas. However, as I remember, the magnetic field lines of a solenoid does travel in a straight line going outward and then curving back going to the opposite pole. So it does not travel in a straight line but acts like a loop/ring clipped into the north pole and connecting to the south. In the solenoid the "rings" of the magnetic field lines would radiate outward with each end at each pole.

    This being the case, is it then possible to "bend" the field lines at one end to magnify or increase the range of the field lines at the other end? :tongue:
    Correct me if I'm wrong please. :biggrin:

    And yes, I am trying to conduct a magnetic field at a distance without loosing too much strength. That is why I want to try to put it in one direction. The bar would need coiling so we're back to the solenoid...
     
    Last edited: May 17, 2007
  15. May 17, 2007 #14

    ZapperZ

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    But the fields are "straight lines" where you are concerned, i.e. far away from the edges of the solenoid! Isn't that what you want?

    Or are you not aware that there are no magnetic monopoles (Div(B)=0 is one of Maxwell equations!)? Thus, magnetic field MUST loop back somehow or else you'll have such sources.

    This question is getting rather weird.

    Zz.
     
  16. May 17, 2007 #15
    All magnetic fields exist in loops. That is one of the most fundamental laws of magnetic fields.

    I don't know what you mean by "need coiling". How is a straight bar of metal similar to a solenoid? If you're just saying you still need a source of magnetism at one end, that's true, but so what? I mean you need a source regardless.

    That's the best I can do, sorry.
     
  17. May 17, 2007 #16

    berkeman

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    Ped, I was referring to the capability of ferrous metals to "attract" and "guide" magnetic field lines. As the others point out, the field has to loop back and connect at some point. But if you want to shape the path of the magnetic field, you can use high-mu material to attract and guide it. Look at how a flat B-field is pulled into a high-mu piece of metal that is inserted into the field. Is that of any help?
     
  18. May 17, 2007 #17

    Ped

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    Xezlec, Berkeman: Thanks, you've been a great help. Maybe my ideas were somewhat unrealistic. I'll stick to the solenoid or the bar magnet. :smile:

    ZZ: Most questions being asked turn out to be weird anyway.
     
  19. Aug 13, 2007 #18
    Hi I am new to the forum and found it while researching on the mentioned subject. It sounds like what you are trying to do is simular to a device patented as a permanet magnet generator. They use small electromagnetic coils to move the magnetic field over larger coils of wire. This generator is supposed to be motionlless and powered only by the permanet magnets. There is still research going on as to the validity of the claim although it was patented in 2002. There are ways to focus magnetic fields using bands or pieces of metal, so your question is valid. The technical implementation of this is beyond my expertise, but I have seen examples of this tecnique being used in commercial magnets. If you want to look at the generator example the patent number is 6362718 and can be viewed on the US Patent Office site.
     
  20. Aug 13, 2007 #19
    Commercial producer of Flux Concentrating Materials

    While brousing I found this (http://www.fluxtrol.com/index.asp?pgid=12) company that produces materials for concentrating magnetic flux lines. Most companies are eager to asist someone experimenting in their field of expertise. You may try contacting them for information concerning your project or question.
     
  21. Sep 19, 2007 #20

    Ped

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    thank you Icemm, its a great help! but you are right..the technichalities involved is quite complicated. I guess I will have to work out the details...
     
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