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Homework Help: Electric field of a point of charge

  1. Sep 2, 2008 #1
    1. The problem statement, all variables and given/known data
    A point charge Q = 16.5uC is at the origin. Find the electric field vector at the point P with coordinates x = 15cm, y = 25cm, z = 0.


    2. Relevant equations

    E = kQ/d^2
    F = QE


    3. The attempt at a solution

    Ok, so first to calculate the distance between the origin and point P I used the Pythagorean theorem, which comes out to be 29.15cm, or .2915m

    Then I applied the formula above

    [(9 x 10^9) (16 x 10^-6)] / [(.15)^2 + (.25)^2] which is equal to --->>> 1694117.647 N/C

    so my question is
    in order to get the electric field do I just multiply
    (1694117.647) (16 x 10^-6) --->>> 27.11

    it just doesn't seem right...
    thanks
     
  2. jcsd
  3. Sep 2, 2008 #2
    why dont you break it down for us and tell us what all these numbers and equations mean.
     
  4. Sep 2, 2008 #3
    1694117.647 N/C is the amplitude of the field vector at that point.
    The direction of the vector is parallel to the hypotenuse.
     
  5. Sep 2, 2008 #4
    Ok I see, thanks
     
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