Statics Homework problem - Reactions of Ball and Socket

AI Thread Summary
The discussion revolves around solving a statics homework problem involving a pipe assembly with vertical loads, requiring the determination of reactions at a ball and socket joint and tensions in cords BC and BD. The participant calculated unit vectors and drew a free body diagram but is uncertain about the correctness of their tension values and the reactions at point A. They express confusion regarding the moments at the ball and socket joint, questioning if the moment should indeed be zero. Another contributor suggests that taking moments around point A could serve as a useful verification method. The conversation highlights the challenges of visualizing the problem due to discrepancies in the diagram's dimensions.
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Homework Statement


The pipe assembly shown in the picture supports the vertical loads shown. Determine the reactions at the ball and socket joint (point A) and the tension in the two cords BC and BD.

ip18h2.jpg

Homework Equations


Sum of Forces = 0
Sum of Moments = 0

The Attempt at a Solution


I first caluclated the unit vector for the BC and BD connections and then I drew a free body diagram at point B. I've attempted many differ way to go about this, but none of them seem right. I came up with the Tensions BC and BD being equal (and opposite) to 12.6 kN though that's probably not right.

I'm not sure about the reactions at point A, because I thought that any moment around a ball and socket is zero?

I've been stuck on this for days and it's due tomorrow at 3!

Please help me,
Thanks so much
 
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The ball and socket joint can only push in the AB direction. My instinct is telling me that A is the point the moments should be taken from. Certainly the sum of the moments there is zero or it would turn. Anyway doing it that way would be an excellent check on your work.
Curious, I see in the diagram that BC and BD are in the horizontal plane but the diagram dimensions indicate B is only half as high as C and D.
 
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Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
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