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Question regarding a charge problem

  1. Feb 9, 2005 #1
    Three charges are fixed to an xy coordinate system. A charge of +18 microC is on the y axis at y = +3.0m. A charge of -12 microC is at the origin. Lastly a charge of +45 mircoC is on the x axis at x = +3.0m. Determine the magnitude and direction of the net electrostatic force on the charge at x = +3m. Specify the direction relative to the -x axis.

    With this problem ^ I am not really sure I understand how to set it up, if they want the force on the x axis, why do they give me the y coordinate and the charge? I tried setting it up with the f= (kq1q2)/r^2 but once I found the two forces using the origin charge as the q2 I wasnt really sure how to move forward.

  2. jcsd
  3. Feb 9, 2005 #2


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    How about writing the 2 vectors with their 2 components clearly stated and them add them "on components".I'm sure it won't fail.

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