# Normal Stress In A Simple Beam

1. Jun 17, 2013

### Baumer8993

1. The problem statement, all variables and given/known data
In a prismatic bar (same cross sectional area throughout the entire length), the load applied to both ends is 100 N causing the member to be in tension. If the cross sectional area of the member is
5 cm2. What is the normal stress in the in kPa?

2. Relevant equations
stress = force / area

3. The attempt at a solution

I first tried without looking at the units, and got 20, which is wrong. I next tried converting everything to m2 to get the answer is pascals the convert to kPa. I got 200 for my second answer. What am I doing wrong? This seems like such a simple problem!

2. Jun 17, 2013

### SteamKing

Staff Emeritus
What are the derived units of a Pascal? Are they N/m^2 or N/cm^2?

3. Jun 17, 2013

### Baumer8993

They are N/m^2. I used an online converter to check, so I confused about what I did wrong.

4. Jun 17, 2013

### barryj

Is the bar supported in the middle? If so, should the force be 100 or 200 N?
How did you get 20?