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Homework Help: The 6.9 N weight is in equilibrium under the

  1. Apr 20, 2010 #1
    1. The problem statement, all variables and given/known data

    The 6.9 N weight is in equilibrium under the
    influence of the three forces acting on it. The
    F force acts from above on the left at an angle
    of α with the horizontal. The 5.1 N force acts
    from above on the right at an angle of 51◦ with
    the horizontal. The force 6.9 N acts straight down.
    What is the magnitude of the force F?
    Answer in units of N.

    2. Relevant equations

    ΣF=0

    3. The attempt at a solution

    I broke the forces up into x and y components so:

    ΣFy=6.9-5.1sin51°+Fsinα and ΣFx=5.1cos51°-Fcosα

    What do I do now?
     
  2. jcsd
  3. Apr 20, 2010 #2

    rock.freak667

    User Avatar
    Homework Helper

    You know for equilibrium ΣFy=0 and ΣFx=0

    So you have two equations with two unknowns, solve them and find the unknowns.
     
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