Given Moment about a Pin and a Roller

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The discussion revolves around solving a statics homework problem involving a beam supported by a pin and a roller. The main focus is on drawing the correct free body diagram and applying equilibrium equations to find support reactions at points A and B. Participants clarify that pin connections do not support moments, leading to the conclusion that the moments at the supports are zero. The conversation emphasizes the importance of using a single moment equation to derive one support reaction and then applying force equilibrium to find the other. Ultimately, the significance of the moment's position is discussed, revealing that it does not affect the reaction values due to the nature of the applied moment being a couple.
  • #31
oh, alright. Well thank you so much, I really appreciate it!
 
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  • #32
hdp12 said:
no there were not, simply the moment is acting on that point at the rigid body between the roller, A, and the pin, B. It's then necessary to find the support reactions at A and B, which are RAY, RBY, and RBX
I'm glad SteamKing seems to understand it because I still don't. If A is a roller, how is it going to supply the downward force necessary to oppose the applied moment? I see no mention of mass or gravity.
I note that the bases of the supports are drawn differently, but not according to any diagrammatic convention I know.
 
  • #33
haruspex said:
I note that the bases of the supports are drawn differently, but not according to any diagrammatic convention I know.

It's possible the support at A was drawn slightly differently to permit the x-axis to be drawn on the diagram w/o interference.

To me, it looked like both supports were pinned connections with no indication of any rollers present.
 
  • #34
SteamKing said:
It's possible the support at A was drawn slightly differently to permit the x-axis to be drawn on the diagram w/o interference.

To me, it looked like both supports were pinned connections with no indication of any rollers present.
The text says A is a roller.
 
  • #35
haruspex said:
The text says A is a roller.
What text? The OP simply posted a pitcher out of his textbook. He put the word "roller" in the thread title, but ... :rolleyes:
 
  • #36
SteamKing said:
What text? The OP simply posted a pitcher out of his textbook. He put the word "roller" in the thread title, but ... :rolleyes:
Post #3
 

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