Question

The strain is $0.01$%. Young's modulus for the material of the wire is $20\times 10$${}^{10}$ N/m${}^2$. The stress on the wire is :

• A. $5\times 10$${}^4$ N/m${}^2$
• B. $20\times 10$${}^4$ N/m${}^2$
• C. $20\times 10$${}^6$ N/m${}^2$
• D. $20\times 10$${}^8$ N/m${}^2$

Answer 1

Answer: (C)

$20\times 10$${}^6$ N/m${}^2$

$ϵ=0.01$ %
$={10}^{-4}$
$y=20\times {10}^{10}N/m^2$
$\sigma =y\times ϵ$
$=20\times {10}^{6}N/m^2$