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Homework Help: Question about electrostatic forces

  1. Nov 4, 2007 #1
    Two identical conducting spheres, fixed in place, attract each other with an electrostatic force of 0.0864 N when their center-to-center separation is 70.6 cm. The spheres are then connected by a thin conducting wire. When the wire is removed, the spheres repel each other with an electrostatic force of 0.0422 N.



    Of the initial charges on the spheres, with a positive net charge, what was (a) the negative charge in coulombs on one of them and (b) the positive charge in coulombs on the other?



    Attempt at solution

    All I could figure out so far has been:

    kq1(before)q2(before)/r^2=-0.0864
    kq1(after)q2(after)/r^2=0.0422
    q1(before)+q2(before)=q1(after)+q2(after)

    What doesn't make sense to me is I thought after a wire is but between two objects, the charges become the same.
     
  2. jcsd
  3. Nov 4, 2007 #2
    Nevermind. I was getting confused. I don't no how to delete a post, but don't respond to this.
     
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