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Homework Help: Electric field produced by 2 point charges

  1. Feb 27, 2009 #1
    1. The problem statement, all variables and given/known data

    A small object A, with a charge of -2.78x10^-10 C, creates an electric field. At a point P located 0.250 m directly north of A, the field has a value of 40.0 N/C directed to the south. If a second object B with the same charge as A is placed at 0.250 m south of A (so that objects A and B and point P follow a straight line), what is the magnitude of the total electric field produced by the two objects at P?

    So basically:

    B<----0.250m----A<----0.250m---->P

    Not N-S but same idea.

    2. Relevant equations

    E=k(q/r^2)

    3. The attempt at a solution

    Well, I don't know if electric fields add like vectors. I worked out the electric field produced by B, at point P, is about 10 N/C south. Given its only asking for magnitude, would it be correct to add the two fields together to get the net field at point P to be 50 N/C?
     
  2. jcsd
  3. Feb 27, 2009 #2
    Took a stab at it. I was correct. Thanks regardless.
     
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