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Homework Help: Weight & Forces

  1. Feb 11, 2009 #1
    1. The problem statement, all variables and given/known data

    A painting hangs from two identical silk ropes that form an angle of 120º. Both ropes make forces of 400 N each to keep it in place.

    2. Relevant equations

    a. Find the combined force of both silk ropes.(I have already done it)
    b. How heavy is the painting?(need help in this one)

    3. The attempt at a solution
    I dont know what the Formula I have to use, to resolve the second one.
     
    Last edited: Feb 11, 2009
  2. jcsd
  3. Feb 11, 2009 #2

    LowlyPion

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    Homework Helper

    Welcome to PF.

    I think you will want to draw a picture yourself and resolve the forces on the ropes into x,y components.

    Since everything is in equilibrium then the horizontal forces will cancel and be equal. The vertical force components then must support the weight.
     
  4. Feb 11, 2009 #3
    is the resultant of both forces equal to the weight?
     
  5. Feb 11, 2009 #4

    LowlyPion

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    That would be another way to do it.
     
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