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Electric/magnetic lines of force's fundamental property.

  1. Jun 4, 2009 #1
    Sources say if lines are parallel they will repel else try and merge which I don't agree and even see practically.

    Suppose we have 2 opposite charges facing each other, the lines are parallel, they should repel.

    Similarly if 2 equal charges are facing each other, the direction of the lines of forces will be opposite, yet they will repel.

    Considering all scenarios...and thus analysing the behaviour of the lines of forces I came to the following conclusion -

    Electrical lines of forces will repel each other if its origin is from the same polarity of charge, else they'll attract.
  2. jcsd
  3. Jun 4, 2009 #2

    Point charges have no effective parallel lines of force....infinite flate plates do...but attraction or repelling depends on charge potential not on parallel nor non parallel lines of force.
  4. Jun 4, 2009 #3


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    Fields do not interact with each other, but they will interact with charged particles via the Lorentz force and multiple sources and inhomogeneities will affect the field distributions but in a manner that satisfies superposition.

    [tex]\mathbf{F} = q\left( \mathbf{E}+\mathbf{v}\times\mathbf{B} \right)[/tex]
  5. Jun 5, 2009 #4
    That means I'm right....right?
  6. Jun 5, 2009 #5


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    No, like Naty1 stated, what you have said is more or less incomprehensible. There is no such thing as force lines, these are as imaginary as field lines. You seem to be implying that these force lines interact with each other which is not true. Fields do not interact with each other, except by combining via linear superposition, they interact with the sources. These interactions are dictated by the Lorentz force.
  7. Jun 5, 2009 #6
    Oh...just as I was thinking...a field does not actually get disturbed by another field its that the other field has some influence on whatever charges lie on that piece of space.

    Considering that 2 fields can exist at a point in space.

    So am I right to conclude the properties of lines of forces?...though they are virtual, are their behaviours such?
  8. Jun 7, 2009 #7
    Anyone to confirm this pls?
  9. Jun 8, 2009 #8
    No one?
  10. Jun 9, 2009 #9


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    I don't know about the rest of the readers but I still have no idea what you're saying about lines of force...
  11. Jun 10, 2009 #10
    Thanks for the notification...that qualifies for a new and clearer way to reconstruct the problem.
  12. Jun 10, 2009 #11


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    I don't know what you are saying about the lines of force, but it doesn't really matter much. The lines of force are not real in any sense, they are simply a graphical aid for plotting the field on a piece of paper and getting a rough understanding of the behavior of the system.

    However, Maxwell's equations are linear, so they obey the principle of superposition. The field due to two sources is the sum of the field due to each individual source.
  13. Jun 10, 2009 #12
    Yeah, as I was saying here -

    Am I right?

    So the lines of forces are the 'resultant'.

    If the properties of the lines of forces are 100% clear, it can be reconstructed completely given few charges/MFs.

    Anyway, I'll post a new question in a clearer form.
  14. Jul 26, 2009 #13
    As a researcher of magnetic behavior in electric machines and devices,i have built an experiment to test exactly this effect. Parallel / same direction "Lines" DO repel and parallel / opposite Lines merge or, as in the test,have zero effect. One would expect some attraction effect, but there is none. I have found nothing that explains exactly WHY this is true.
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