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Homework Help: Pith ball lab.

  1. May 27, 2005 #1
    Pith ball lab. HELP

    In the lab there are 2 balls that are being seperated by an electrostatic force.
    Since both of the balls are receiving the same force it is only neccesary to find the force on one of the balls.

    So here goes. The formula I am using is Fe=k q/r(squared)

    I know k= 9.0 x 10^9
    R= 7.3 cm or .073m
    and the angle is 20* for one side
    I believe I need to find tension in the string. And find the horizontal component so I can find Fe because those 2 are equivalant. I am just not sure how to do it. :uhh:

    Thanks for the help!
    Last edited: May 27, 2005
  2. jcsd
  3. May 27, 2005 #2
    I know someone knows this.
  4. May 27, 2005 #3
    Drawing a force diagram for one of the balls will be the most helpful thing in this situation. Also, note the electrostatic force depends on BOTH charges, so its kqq/r^2. What exactly are you trying to find? Isolate this force from the force diagram. Then from there you can solve for whatever unknown you have.
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