Geometry in a Truss: Find Internal Forces & X

[mjan8468]

I'm to work out the internal forces in this truss. I know to get the reaction forces first, so I take the moment at the pin support to find the reaction at the roller support. I can't get my head around at how to find x through the geometry to add that force to the moment though. Is there not enough information in the diagram to find it? Or am I missing something simple?

 

[Studiot]

Yes you need the 'rise' or vertical height of the truss as well as the span. Alternatively you need the pitch (angle to the horizontal) of the roof.

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[SteamKing]

Look at the truss carefully. What kind of triangle is formed by the members in the center of the truss?

 

[Studiot]

Look at the truss carefully...

Well spotted steamking you are spot on.

 

[alphy]

I would suggest using the principles of statics and trigonometry to solve for the internal forces and X in the truss. By taking the moment at the pin support, you have correctly found the reaction at the roller support. To find X, you can use the method of joints or method of sections to analyze the forces acting on the truss and solve for X. It is possible that there may not be enough information in the diagram to solve for X, in which case additional measurements or assumptions may need to be made. It is also important to ensure that all forces and moments are accounted for and in equilibrium to accurately solve for X. I would recommend consulting with a mathematics or engineering expert for further assistance in solving this problem.