**Question:**

**A steel rail of length $5 \mathrm{~m}$ and area of cross-section 40 $\mathrm{cm}^{2}$ is prevented from expanding along its length while the temperature rises by $10^{\circ} \mathrm{C}$. If coefficient of linear expansion and Young’s modulus of steel are $1.2 \times 10^{-5} \mathrm{~K}^{-1}$ and $2 \times 10^{11} \mathrm{Nm}^{-2}$ respectively, the force developed in the rail is approximately:**

$2 \times 10^{7} \mathrm{~N}$

$1 \times 10^{5} \mathrm{~N}$

$2 \times 10^{9} \mathrm{~N}$

$3 \times 10^{-5} \mathrm{~N}$

Question of from chapter.

JEE Main Previous Year Online April 9, 2017

Correct Option: 2

**Solution:**