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Homework Help: Net Electric Field

  1. Jan 17, 2005 #1
    Two charges are placed on the x axis. One charge (q1=+8.45 mC) is at x1=+2.55 cm and the other (q2=-21.4 mC) is at x2=+9.01 cm. Find the magnitude of the net electric field at x=6 cm.

    I used this equation:
    (x is in cm)

    (N/C) = {(k * 8.45*10^-6) / [(x+2.55)^2 / 100]} - {(k * 21.4*10^-6) / [(x-9.01)^2 / 100]}

    and my solution is not correct.
     
  2. jcsd
  3. Jan 17, 2005 #2

    dextercioby

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    Did u add the 2 vectors correctly??Post the first part of your calculations.It's essential.

    Daniel.
     
  4. Jan 17, 2005 #3
    figured it out, thx.
    i just needed to change
    some signs in that equation.
     
  5. Jan 17, 2005 #4

    dextercioby

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    Well,u see,that's why it was important to check your initial setting...Some or maybe one sign wrong can make a whole lot of difference,and with vectors u always have to keep an eye out...

    Daniel.
     
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