Question

The area of cross section of a wire is ${10}^{-6}{m}^2$.When its length is increased by $0.1$%, a tension of $1000N$ is produced. The young's modulus of the wire will be :

• A. ${10}^{12}N/m^2$
• B. ${10}^{11}N/m^2$
• C. ${10}^{10}N/m^2$
• D. ${10}^{9}N/m^2$

Answer 1

The correct option is A ${10}^{12}N/m^2$

$T=F=1000N,\Delta L=\frac{L}{1000}$
$Y=\frac{FL}{A\Delta L}$$=\frac{1000\times 1000}{{10}^{-6}}$$={10}^{12}N/m^2$