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Homework Help: Electric force angles problem

  1. Mar 30, 2008 #1
    Electric force angles problem :(

    1. The problem statement, all variables and given/known data
    Three positive particles of charges 11.0 µC are located at the corners of an equilateral triangle of side d = 14.0 cm (Fig. 16-38). Calculate the magnitude and direction of the net force on each particle.
    Fig. 16-38

    2. Relevant equations
    F = KQ_1Q_2/r^2

    3. The attempt at a solution
    F = KQ_1Q_2/r^2
    F = (9X10^9)(1.1X10^-5)^2/.14^2
    F = 55.561 N for all points - Q1, Q2, and Q3 (correct)

    Q1 angle = 90 degrees (correct)
    Q2 angle = ?
    Q3 angle = ?

    I need to find the directional angle for particles Q2 and Q3 - I am unsure how to find these. I was thinking I might have to draw a triangle?

  2. jcsd
  3. Mar 30, 2008 #2
    It's an equilateral triangle.

    [tex]\angle Q_1=\angle Q_2=\angle Q_3[/tex]

    [tex]\angle Q_1+\angle Q_2+\angle Q_3=180[/tex]
  4. Mar 30, 2008 #3
    I'm not looking for the interior angles, I'm looking for the angle of direction of force on Q2 and Q3.
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