# Homework Help: Free Body Diagram Beam forces

1. Oct 23, 2011

### Ntothaate

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

This is not a homework problem, but something i cant figure out how to calculate. Basically I have what is similar to a cantilever beam setup with an extension. what i need to figure out is what the vertical forces are at the two points(triangles on the attached paint drawing), and how I would Calculate that. There is no force added at any point, so it needs to be calculated solely off the mass of the beam. I dont know the mass so at this point i can just make one up as M=1lb, or whatever unit you would like. thank you in advance

2. Relevant equations

3. The attempt at a solution
1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

#### Attached Files:

• ###### beam.jpg
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2. Oct 23, 2011

### 256bits

This is a static problem so the sum of moments calculated about a point = 0.
And the sum of forces upward = sum of forces downward.

You would use the cg as to where the force of the beam acts. Note that you have 2 centres of gravity - one on the length = 9 and one on the length = 1. If M=1 then on the length 9 , the force of 0.9 acts downward at a location halfway of its length (9) from the up pointing triangle, and the part of the beam of length 1, has its cg at the 0.5 mark acting with of force of 0.1 downward.
Does that help?

Last edited: Oct 23, 2011
3. Oct 23, 2011

### Ntothaate

I believe i can figure it out, thanks for the help 256bits