calculate the force equilibrium in members of BE and BF on this truss (attached image)

Question

anonymous · Answer

attachment

anonymous · Answer

does the red arrow show the direction of 14kN force?

anonymous · Answer

yess...
the force is 14KN downward

badhi · Answer

These are the steps that I would follow,

1) Starting from the right end (node D) mark the direction of the forces along the members connecting to that node considering the equilibrium of the node. (Guessing the directions of the forces can be easily done if there are only three forces on a node)

2) Consider the node C. There cannot be three nodes under stress that are perpendicular to each other there fore, you can consider one member is having zero stress (you have to find which one).

3) As in node D find the directions and the sizes of the forces in the node E. There you'll find the stress of the member BE. 

4) from node B find the stress of the BF, using the equilibrium principle