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Does the difference in charge play a role in electromagnetism such as

  1. Sep 22, 2008 #1
    does the difference in charge play a role in electromagnetism such as a +8 charge pulling a -1 being stronger because of the difference in numbers or does that even matter i mean would that mean that that is stronger compared to a + 1 charge pulling a -1 charge. Thanks in advance.
     
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  3. Sep 22, 2008 #2

    atyy

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    Re: electromagnetism

    Yes, it matters: F=kq1q2/r2

    It might be interesting to consider the motion of a test charge between two infinitely large parallel conductors. Does (+1,-1) and (+2,0) produce the same result?

    I'm not sure I've that up correctly, but take a look at the method of images:
    http://farside.ph.utexas.edu/teaching/em/lectures/node64.html
     
  4. Sep 22, 2008 #3

    tiny-tim

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    Coulomb's law

    Hi cam875!

    It's not the difference in charge, but the product of the charges, that matters (and also the distance, of course :wink:).

    So a +8 and a -1 (or a -8 and a +1) pull each other twice as strongly as a +4 and a -1.

    See Coulomb's law :smile:
     
  5. Sep 22, 2008 #4
    Re: electromagnetism

    cool thanks for the help very interesting. so are u saying that because (+8) + (-1) is 7 and (+4) + (-1) is 3 that there is a little more than double the attraction in the first example.
     
    Last edited: Sep 22, 2008
  6. Sep 22, 2008 #5

    atyy

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    Re: electromagnetism

    No. I believe what tiny-tim is very correctly saying is in the first example, the attraction between two point charges a fixed distance apart ~(+8)(-1)=-8 units, in the second example, the attraction is ~(+4)(-1)=-4 units. So the attraction is exactly double in the first example compared to the second.

    I really second his recommendation that you look up Coulomb's law.:smile:
     
  7. Sep 23, 2008 #6

    tiny-tim

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    atyy atyy atyy!

    I agree entirely with atyy. :biggrin:
     
  8. Sep 23, 2008 #7
    Re: electromagnetism

    oh ok so your multiplying the charges instead of adding them. makes sense and im going to look at that law, thanks for the help.
     
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