Mechanics Help: Proving That θ = 45°?

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The discussion revolves around a mechanics problem requiring proof that θ = 45°. The user has attempted to resolve forces acting on beads using tension and weight equations but is unsure how to proceed after establishing some initial equations. Key points include the need to consider the maximum horizontal force of friction acting on the beads and how the distance between beads A and B affects the problem. Additional guidance suggests focusing on the horizontal forces balancing the tension for both beads. The user is encouraged to clarify the role of friction and the conditions for the beads' positions to advance in solving the problem.
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Mechanics help please!

Hi, can anyone help me with the following mechanics question:

http://tinypic.com/f1iogj.jpg"

I've attempted this question but I'm stuck on how i can prove that θ = 45° :confused:

I've constructed a diagram but I haven't scanned it but what I've got so far is from the diagram at point C, by resolving horizontally i find that the tensions, say T1 and T2 are equal to each other and I label this as T.

Resolving vertically I get 2T cos θ - w = 0

for the bead on the far left, by resolving horizontally I got:

F1 - T1 sin θ = 0 (F1 being the force acting towards the left)

vertically I get: N1 - T1 cos θ - w = 0


For the bead on the far right
, by resolving horizontally I get:

F2 - t2 sin θ = 0

vertically:

N2 - T2 cos θ = 0

And this is where I'm stuck...I don't know where to go from here. Am I on the rght track? Can anyone help? Thanks! :confused: Sorry again that I haven't provided my diagram :frown:
 
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Ok, a couple things here that you need to work on.

Sorry, I misread the question, ignore my first comment (which I have now deleted).

Second, you left out the weight in the vertical force equation for the point B on the far right.

Third, you need to figure out how the condition that the beads A and B be as far apart as possible plays into things. Here is a hint: what is the maximum horizontal force of friction that bead A can feel? What about bead B?
 
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hmm I still don't understand...:confused:
 
Where does the horizontal force on bead A that balances the tension come from? What is the maximum value this force can have? Answer the same thing for B.
 
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