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Homework Help: Finding net electric potential, i got it set up right, but somthing is f'ed up!

  1. Sep 25, 2005 #1
    Hello everyone I think i set this up properly but the answer is still wrong. I tried 2 different ways, both wrong.
    In Figure 24-33, what is the net electric potential at point P due to the four particles, if V = 0 at infinity, q = 5.50 fC, and d = 3.00 cm? Figure 24-33
    I used potential due to a group of point charges. V = The sum of all the point charges.
    V = 1/(4pi*Eo)(q1/r + q2/r + q3/r + q4/r);
    V = 1/(4pi*Eo)(5.50/.03 + 5.50/.03 + 5.50/.03 + 5.50/.03);
    V = 6.59x10^12 V;
    Which was wrong so i noticed that 2 of the charges q, where negative, so I tried:
    V = 1/(4pi*Eo)(5.50/.03 + 5.50/.03 + (-5.50/.03) + (-5.50/.03));
    V = 0 V; Wrong again.
    What am I doing wrong? Is it because q = 5.50 fC? I have no idea what f stands for? is it 10^-15 or what? :bugeye:
     
  2. jcsd
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