# Homework Help: Finding the forces of a truss

1. Dec 18, 2011

### naruto631

1. The problem statement, all variables and given/known data

i am trying to figure out the forces of the different members of this truss in which looks like a a square that is split into two triangles and is affixed to another triangle the same size I have already found the moment of the reactions and already found the reaction forces as well.

Code (Text):
A -500lbf  C -500lbf

2ft           2ft
--------l----------- l Pin Reaction E
\         l          /     l
\       l        /       l   2ft
\     l      /         l
\   l    /           l
\ l  /---------l Roller reaction D
B
2. Relevant equations
sin
cos
tan
Efx=0
Efy=0
Em=0

3. The attempt at a solution
more or less it is a question about the method of joints but im not exactly sure how you do it. Also the triangles are all 45° 45° and 90°

Last edited: Dec 18, 2011
2. Dec 18, 2011

### Staff: Mentor

It is not clear, is your truss is made of 4 straight pieces, or 7? To what do the lbf refer?

If you wish to use ASCII art (and I don't recommend it), then you must include it within [code] [/code] pair. Otherwise the forum software squashes strings of spaces into a single space. You'll find it easiest if you also use Courier fixed-size font.
Code (Text):
[font="courier new"]
|
-----------------------|
\          |          /|
\        |        /  |
\      |      /    |
\    |    /      |
\  |  /        |
\|/          |
-----------------------'
[/font]

3. Dec 18, 2011

### naruto631

thank you and your picture is pretty much accurate without that line extending after B though

4. Dec 18, 2011

### Staff: Mentor

Point B is unsupported and in mid-air, is it?

What and where are points A and C?

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