Answer:
Option D is the correct answer.
Explanation:
We equation for elongation
[tex]\Delta L=\frac{PL}{AE}[/tex]
Here we need to find weight required,
We need to stretch a steel road by 2 mm, that is ΔL = 2mm = 0.002 m
[tex]A=\frac{\pi d^2}{4}=\frac{\pi ({4\times 10^{-3}})^2}{4}=1.26\times 10^{-5}m^2[/tex]
E = 200GPa = 2 x 10¹¹ N/m²
L=2m
Substituting
[tex]0.002=\frac{P\times 2}{1.26\times 10^{-5}\times 2\times 10^{11}}\\\\P=2520N=256.4kg[/tex]
Option D is the correct answer.
