Use two elements of equal length to determine the natural frequencies and mode shapes in flexure of a shaft modeled as a simply supported beam. The length of the shaft is \(1 \mathrm{~m}\), \(E=100 \mathrm{GPa}, A=10^{-3} \mathrm{~m}^{2}, I=10^{-7} \mathrm{~m}^{4} ; ho=4000 \mathrm{~kg} / \mathrm{m}^{3}\).