Question

Which one of the following is the Young's modulus for the wire having stress-strain curve shown in the figure.

• A. $24\times {10}^{11}$
• B. $8.0\times {10}^{11}$
• C. $10\times {10}^{11}$
• D. $2.0\times {10}^{11}$

Answer 1

The correct option is D $2.0\times {10}^{11}$

Young's modulus is defined only in elastic region and
$Y=\frac{\text{Stress}}{\text{Strain}}=\frac{8\times {10}^7}{4\times {10}^{-4}}=2\times {10}^{11}N/m^2$