# Homework Help: Youngs modulus

1. Sep 1, 2011

### TyErd

1. The problem statement, all variables and given/known data
Question simply asks to calculate the Youngs modulus. I've attached the question.

2. Relevant equations
Youngs Modulus = (change in stress)/(change in strain)

3. The attempt at a solution
okay, what i did was simply find the gradient between each of the points. However they were all different gradients, which means the graph isn't linear (i think). So then how do i solve it?

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Last edited: Sep 1, 2011
2. Sep 1, 2011

### PeterO

I believe Youngs modulus can only be calculated for stress-strain that remains below the elastic limit - ie the first straight part of the graph.

EDIT: btw, I don't see the question attached, but hopefully this will help anyway.

3. Sep 1, 2011

### TyErd

sorry about that, I've attached the question now.

4. Sep 1, 2011

### PeterO

What did you make of the statement in the first sentence?

5. Sep 1, 2011

### TyErd

Oh i get it, the first data point would be 0 stress 0 strain and the gradient between 0,0 and the 1st data point is the same as the gradient between the first data point and the second data point but different from the 2nd and 3rd. I get it, thank you!

6. Sep 1, 2011

### PeterO

well done.

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