How to get mag. & angles of resultant couple moment

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To determine the magnitude and direction of the resultant couple moment from two valve handles, the moments generated by each handle must be calculated using the formula M = (d)(F), where d is the distance and F is the force. The calculated moments are MA = 6.125 Nm and MB = 4.375 Nm. It is essential to consider the direction of these moments as they are vector quantities, which can be found using the cross product formula \(\vec{M} = \vec{r} \times \vec{F}\). The angle of the wheel on the right at 60 degrees from the y-axis is also a critical factor in determining the resultant moment's direction. Properly combining these vector moments will yield the resultant couple moment's magnitude and direction.
caddyguy109
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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

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:

M=(d)(F)
MA=(0.175m)(35N)=6.125Nm
MB=(0.175m)(25N)=4.375Nm

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