Which material has the greatest Young's Modulus?

[songoku]

Homework Statement

Please see below

Relevant Equations

Young Modulus = stress / strain

My answer is (B) since it has the highest slope for the straight line part of the graph but the answer key is (A). Is it because the slope of graph B will decrease until the value less than slope A? So we don't only consider the straight line part but the whole graph?

Thanks

 

[haruspex]

Homework Statement: Please see below
Relevant Equations: Young Modulus = stress / strain

View attachment 332269

My answer is (B) since it has the highest slope for the straight line part of the graph but the answer key is (A). Is it because the slope of graph B will decrease until the value less than slope A? So we don't only consider the straight line part but the whole graph?

Thanks

According to https://en.wikipedia.org/wiki/Young's_modulus, it is the slope of the elastic portion (the linear part at the start) of the curve. That makes B correct.

 

[songoku]

Thank you very much haruspex