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: Electrostatic force and magnitude problem

  1. Sep 2, 2011 #1
    In the figure, the net electrostatic force on Q1 is zero. If Q1 = +4.99 nC, determine the magnitude of Qo.


    Qo = (r0/r1)^2 * abs(q)*2cos theta

    The figure is attached, please help, I'm so lost with physics II
     

    Attached Files:

  2. jcsd
  3. Sep 2, 2011 #2

    tiny-tim

    User Avatar
    Science Advisor
    Homework Helper

    hi loganblacke! :smile:

    (have a theta: θ and try using the X2 icon just above the Reply box :wink:)

    forces are vectors, so you have to add them as vectors

    start by writing out the three forces as three vectors :smile:
     
  4. Sep 2, 2011 #3
    How do i determine the direction of the vectors?
     
  5. Sep 2, 2011 #4

    tiny-tim

    User Avatar
    Science Advisor
    Homework Helper

    each vector will point along the line between the two charges :smile:
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook