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Homework Help: Find the y-compnent of the force

  1. Oct 21, 2008 #1
    1. The problem statement, all variables and given/known data
    Object A, which has been charged to + 21.2nC , is at the origin. Object B, which has been charged to + 19.7nC , is at (x,y)= (0cm, 2.80cm) .

    What is the y-component of the force (F a on b)y on B due to A

    2. Relevant equations

    F=K(q1)(q2)/(r^2)

    3. The attempt at a solution

    F= (9*10^9)*(21.2*10^-9)*(19.7*10^-9)/(.028^2)
    = .0047N

    Where am I messing up? Thanks
     
    Last edited: Oct 21, 2008
  2. jcsd
  3. Oct 21, 2008 #2

    LowlyPion

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    From your statement of the problem I get 4.8*10-3 N in the positive y direction.

    Which is seemingly about the same as yours. Is there a preference for how the answer should be entered perhaps?
     
  4. Oct 21, 2008 #3

    tiny-tim

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    EDIT: oops! misread it. :redface:

    Thanks, LowlyPion! :smile:

    (though why does the question bother to ask for the y-component if everything's on the y-axis anyway? :rolleyes:)
     
    Last edited: Oct 21, 2008
  5. Oct 21, 2008 #4

    LowlyPion

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    Edit: Agreed. The wording of the OP seems more designed to encourage careful reading than grasping the concepts. I suppose it is preparation for latter problem statements.
     
    Last edited: Oct 22, 2008
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