Statics question (is this possible?)

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The discussion revolves around a statics problem involving a frame at a 45-degree angle and whether it can remain stationary if unpinned at point A, assuming it is massless. Participants agree that the frame would indeed stay stationary under these conditions, although they note that this scenario is impractical as it does not represent a stable equilibrium. The conversation highlights the importance of considering the frame's mass, as any weight would cause it to move downhill. There is also a humorous acknowledgment of the forum rules regarding posting solutions. Overall, the thread emphasizes conceptual understanding over strict problem-solving.
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Homework Statement


upload_2016-3-9_3-26-45.png

Homework Equations

The Attempt at a Solution


for part b, where the angle is 45 degrees.

upload_2016-3-9_3-26-59.png


would this mean that if you unpin the frame at point A, it would stay completely stationary (assuming the frame is massless)?
 
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Yes (frame weightless ?)

What's the attachment for ?
 
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BvU said:
Yes (frame weightless ?)

What's the attachment for ?
Whoops, attachments were added by mistake.

But very interesting to know that it would be stationary. Very hard to imagine it because it is impractical.
 
Impractical in the sense that it isn't a stable equilibrium, but yes: a normal force ##20\;{1\over 2} \sqrt2## at E balances the load forces.

Again, the frame weight should be zero or else the weight will make it go downhill mucho quicko !
 
BvU said:
Impractical in the sense that it isn't a stable equilibrium, but yes: a normal force ##20\;{1\over 2} \sqrt2## at E balances the load forces.

Again, the frame weight should be zero or else the weight will make it go downhill mucho quicko !
Yes, I spent a good minute wondering how the frame would stay stationary on a roller, on a slope because the question didn't mention the frame was massless.
 
As long as they don 't mention the frame mass you should be OK. Witness the book solution (or is it yours?).
 
BvU said:
As long as they don 't mention the frame mass you should be OK. Witness the book solution (or is it yours?).
I posted the textbook solution.
 
:smile: I kind of knew that. The (my) humour is in the sleek way you evade the PF rule that an attempt at solution is required. Never mind. You have a very sensible question about a not so sensible exercise. Time to move on to the next one !
 
BvU said:
:smile: I kind of knew that. The (my) humour is in the sleek way you evade the PF rule that an attempt at solution is required. Never mind. You have a very sensible question about a not so sensible exercise. Time to move on to the next one !
haha, yeah, sorry, I should have posted my attempt but figured the textbook solution was much easier to read and my question was conceptual instead of asking if I had the right answer.
 
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All understood, clear and fine. Time to move on to the next exercise !
 

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