Intro Level Question -- Truss Analysis

1. Dec 5, 2015

DiamondV

1. The problem statement, all variables and given/known data
http://puu.sh/lKP9T/b6aea483b5.png [Broken]
http://puu.sh/lKPdk/a99777477e.png [Broken]
http://puu.sh/lKPkj/a9f199e959.jpg [Broken]

My question is the last picture/slide which says F_DB = F_DA how? why is that?

2. Relevant equations
F_DB = F_DA ?????

3. The attempt at a solution

Last edited by a moderator: May 7, 2017
2. Dec 5, 2015

SteamKing

Staff Emeritus
Since the reaction Cx = 0, what does this tell you about the horizontal force in member AB?

3. Dec 6, 2015

DiamondV

Its going to be completely dependent on the 2000lb and 1000lb forces at A and B.

4. Dec 6, 2015

SteamKing

Staff Emeritus
Those are vertical loads. How can they influence what happens in the horizontal direction?

5. Dec 6, 2015

DiamondV

I was thinking of it, that they wont have any components in x. Ah. So the entire 2000lb load is distributed along AD. And the entire 1000lb load is distributed along BD and BE.