Statics Question: Is my answer correct?

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The discussion revolves around a statics problem involving a 70-N force acting on a pipe. The user calculates the moment about point A and finds it to be 73.9 N·m, initially stating it as counterclockwise, but is corrected to clockwise. For part B, the magnitude of the horizontal force needed to produce the same moment is also determined correctly, but the direction of this force must be specified to match the moment's direction from part A. Overall, the user is close to a complete solution but needs to clarify the moment's direction and the applied force's orientation. The conversation emphasizes the importance of accurately defining both magnitude and direction in statics problems.
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Please click the image to enlarge it

http://img257.imageshack.us/img257/3952/problemfy9.th.jpg I think I have this problem solved correctly, but please check my solution. In the image my problem is *4-24
The 70-N force acts on the end of the pipe at B Determine (a) The moment of this force about point A, and (B) the magnitude and direction of a horizontal force, applied at C, which produces the same moment take theta = 60 degrees

This is my solution

M_x\left=-70\cos{60}(0.9)
M_y\left=-70\sin{60}(0.7)

which comes out to 73.9 N*M counter clockwise in the Z

For part B
73.9=Fd with d = 0.9
 
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Mesmer said:
Please click the image to enlarge it

http://img257.imageshack.us/img257/3952/problemfy9.th.jpg


I think I have this problem solved correctly, but please check my solution. In the image my problem is *4-24
The 70-N force acts on the end of the pipe at B Determine (a) The moment of this force about point A, and (B) the magnitude and direction of a horizontal force, applied at C, which produces the same moment take theta = 60 degrees

This is my solution

M_x\left=-70\cos{60}(0.9)
M_y\left=-70\sin{60}(0.7)

which comes out to 73.9 N*M counter clockwise in the Z

For part B
73.9=Fd with d = 0.9
You're almost there, good work. For part A, the magnitude of the moment is correct, but you said it was counterclockwise. It's actually a clockwise moment, with its direction pointing inward into the page along the z axis.
for part B, again your solution for the magnitude of the Force is correct, but you've got to specify the direction of that force (left or right?) to give the same direction of moment as was determined in part A.
 
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PhanthomJay said:
You're almost there, good work. For part A, the magnitude of the moment is correct, but you said it was counterclockwise. It's actually a clockwise moment, with its direction pointing inward into the page along the z axis.
for part B, again your solution for the magnitude of the Force is correct, but you've got to specify the direction of that force (left or right?) to give the same direction of moment as was determined in part A.



Clockwise is negative and CCW is positive. got it!
 
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