A bar made of linear elastic isotropic material is fixed at one end and subjected to an axial force of $1 \mathrm{kN}$ at the other end. The cross-sectional area of the bar is $100 \mathrm{~mm}^{2}$, length is $100 \mathrm{~mm}$ and the Young's Modulus is $1 \times 10^{5} \mathrm{~N} / \mathrm{mm}^{2}$. The strain energy stored in the bar is_____________ $\mathrm{Nmm}$

A bar made of linear elastic isotropic material is fixed at one end and subjected to an axial force of $1 \mathrm{kN}$ at the other end. The cross-sectional area of the bar is $100 \mathrm{~mm}^{2}$, length is $100 \mathrm{~mm}$ and the Young's Modulus is $1 \times 10^{5} \mathrm{~N} / \mathrm{mm}^{2}$. The strain energy stored in the bar is_____________ $\mathrm{Nmm}$

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