1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
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: Point Charge Problem (Not in a straight line)

  1. Sep 13, 2010 #1
    Point charge 2.0 uC is located at X= 0, X= 0.30m , point charge -2.0uC is located at X= 0 Y= -0.30m . What are (a)the magnitude and (b)direction of the total electric force that these charges exert on a third point charge Q= 5.0 uC at X= 0.40 , Y= 0?

    I drew a diagram of what was going on and used Pythagorean theorem to find out that the distance between Q1 and Q is .50m as well as Q2 and Q. I then broke Q into its components and solved for (F1 on Q)x and (F1 on Q)y. But first

    (F1 on Q) = (8.988*10^9)[(2*10^-60 * (5*10^-6)/(.50m)2] = 0.35952N

    (F1 on Q)x= 0.35952N*cos[tex]\theta[/tex] = 0.35952N(.40/.50) = 0.287616N

    (F1 on Q)Y= -0.35952N*sin[tex]\theta[/tex] = -0.35952N(.30/.50) = -0.215712N

    Where do I go from here? And how do I find theta?
  2. jcsd
  3. Sep 13, 2010 #2
    Okay, I got the force but how do I find the angle in degrees clockwise from the +x direction?
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook