Physics - Elasticity Question with Solution | TestHub

A uniform heavy rod of mass$20 \mathrm{kg}$. Cross sectional area$0.4{ \mathrm{m}}^2$and length$20 \mathrm{m}$is hanging from a fixed support. Neglecting the lateral contraction, the elongation in the rod due to its own weight is$x\times {10}^{-9} \mathrm{m}$. The value of$x$is _____ .
(Given. Young's modulus$Y=2\times {10}^{11}{\mathrm{Nm}}^{-2}$and$g=10 \mathrm{m} {\mathrm{s}}^{-2}$)