Problem 005-ms | Method of Sections

Problem 005-ms
The structure shown in Figure T-07 is pinned to the floor at A and H. Determine the magnitude of all the support forces acting on the structure and find the force in member BF.
 

Frame with members under axial force only

 

Solution 005-ms

 

Comments

when do you use (5/squareroot of 41)and when do you use (4/squareroot of 41)

Jhun Vert's picture

The slope is 4 horizontal 5 vertical. For $\Sigma F_x$ use the horizontal or $\frac{4}{\sqrt{41}}$ and for $\Sigma F_y$, use the vertical or $\frac{5}{\sqrt{41}}$.