A steel wire of length \( 2 \, \text{m} \) and Young’s modulus \( 2.0 \times 10^{11} \, \text{N m}^{-2} \) is stretched by a force. If Poisson ratio and transverse strain for the wire are \( 0.2 \) and \( 10^{-3} \) respectively, then the elastic potential energy density of the wire is \( \underline{\hspace{1cm}} \times 10^{5} \) (in SI units).