Steel wire of length L at 40^ C is suspended from the ceiling and...

Steel wire of length $L$ at $40^{\circ} \mathrm{C}$ is suspended from the ceiling and then a mass $m$ is hung from its free end. The wire is cooled down from $40^{\circ} \mathrm{C}$ to $30^{\circ} \mathrm{C}$ to regain its original length $L$. The coefficient of linear thermal expansion of the steel is $10^{-5} /{ }^{\circ} \mathrm{C}$, Young's modulus of steel is $10^{11} \mathrm{~N} / \mathrm{m}^2$ and radius of the wire is $1 \mathrm{~mm}$. Assume that $L>$ diameter of the wire. Then, the value of $m$ in $\mathrm{kg}$ is nearly