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How to get mag. & angles of resultant couple moment

  1. Oct 1, 2005 #1
    I have another thread for another problem, but no one seems to be responding about this second problem, so i'll post it here.

    Need to find the magnitude and direction/space angles of the resultant couple moment of two valve handles being turned, as pictured:
    http://img347.imageshack.us/img347/2488/problem64sx.jpg [Broken]

    Would the resultant mean at the origin of the axes? So far, I've done this, using the left as A and the right as B:


    Should the forces have unit vectors k on them? If what I did is somewhat right, then how do I get the resultant magnitude and direction if the only other piece of data given is that the wheel on the right is angled 60deg. from the y-axis--no other distances, etc?
    Last edited by a moderator: May 2, 2017
  2. jcsd
  3. Oct 2, 2005 #2

    Doc Al

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    Staff: Mentor

    Your magnitudes are correct, but these moments are vectors. What direction do they point? ([itex]\vec{M} = \vec{r} \times \vec{F}[/itex]) Add those vectors.

    (And please don't post the same question in mutliple threads! It's generally best to post one problem per thread.)
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