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Homework Help: Point charges

  1. Feb 5, 2004 #1
    Three identical point charges, each of mass 140g and charge +q, hang from three strings. If the lengths of the left and right strings are each 10 cm, and each forms an angle of 48 degree with the vertical, determine the value of q.
  2. jcsd
  3. Feb 5, 2004 #2


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    Homework Helper

    This is a statics problem. The forces acting on one of the point charges are tension, gravity, and electro-magnetism.

    Of course, you can't solve the problem unless it lets you know what the distance between the point charges is.
  4. Jan 28, 2011 #3
    We do know the distances.. Lsin(theta)
  5. Jan 28, 2011 #4
    use lami's theorm on any of the left and right charge, forces being Tension, mg, electric force
  6. Jan 28, 2011 #5

    Doc Al

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    Staff: Mentor

    Realize that this thread is 7 years old.
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