Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Magnitude/direction of point charges

  1. Sep 3, 2011 #1
    1. The problem statement, all variables and given/known data

    (a) Find the magnitude and direction of the net electrostatic force exerted on the point charge q3 in the figure below. Let q = +1.5 µC and d = 27 cm.

    http://www.webassign.net/walker/19-31.gif

    2. Relevant equations



    3. The attempt at a solution

    I found Fx = 1.7 N and Fy = 3.3 N. So the total magnitude was 3.3 N. This part was correct, however when I tried to find the magnitude usting tan^-1(Fy/Fx) = tan^-1(3.3/1.7) = 62.74 degress the answer is wrong. It says I'm within 10%, but still wrong. I don't understand why. Please help
     
  2. jcsd
  3. Sep 3, 2011 #2

    SammyS

    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper
    Gold Member

    If Fx = 1.7 N and Fy = 3.3 N , then the magnitude of F cannot be 3.3 N

    Show your work so we can help find where you're going wrong.
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook