Young's modulus

[chrisharimlee]

In the passage i am given these 2 formulas:
1) Youngs modulus= stress applied to pole/fractional change in pole length
2) fractional change in pole length= delta length/length of pole

so the question asks a metal pole is subjected to great stress while undergoing relatively little fractional change in length, what happens to the youngs modulus

Note: in the passage they talk of the stress the pole endures due to itself. so for example 5m from the top the bottom portion of the pole is stressed by the portion above it.....

So since they include this i relate stress on the pole to a downward force.
in this case back to the question
The stress is large, and the fractional change is small so the value of the youngs modulus is large.
however how can you differentiate if it is (+) or (-)?
I was thinking that if theres a downward stress the delta length would be negative because the final length is smaller than the original, making the value negative.

The answer they give is (+) large value for Youngs modulus.
Am i thinking to much into this question?

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[Alucard6]

I was never a big fan of the modulus stuff, but I believe Young's modulus should always be positive. It is essentially the ratio of stress:strain. So for it to be negative, there would have to be a negative stress or negative strain.

In this case the material is being stressed, so both values are positive and thus Young's is positive as well.