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Homework Help: Staics help please

  1. Feb 20, 2009 #1
    staics help please!!!

    Please help with this problem.. I'm going crazy.

    I have attempted the problem and i think my methods are correct. however some algebra mistake is also there i think.

    im submitting my work on the thread below

    Question: Determine the resultant moment of the two forces about the Oa axis. express the result as a Cartesian vector.

    The picture is attached.
    Note*: its 80lb that's a bit smudged on the right of the attachment.
     

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  2. jcsd
  3. Feb 20, 2009 #2
    Re: staics help please!!!

    here is my work

    the book answer is : [26.1i - 15.1j] lb*ft
     

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  4. Feb 21, 2009 #3
    Re: staics help please!!!

    Isn't it the perpendicular component of F1 that creates the torque about the Oa axis? Also the [tex]\hat{k}[/tex] in [tex]\vec{m_1}[/tex] seems to be incorrect anyways.
     
    Last edited: Feb 21, 2009
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