고체역학 (Gere) — Analysis of Stress and Strain: Problem 7.3-2

7.3-2 Repeat the preceding problem [7.3-1: The stresses acting on an element are $\sigma_x = 3 \text{ MPa}$, $\sigma_y = 5 \text{ MPa}$, and $\tau_{xy} = 2.8 \text{ MPa}$. Determine the principal stresses and show them on a sketch of a properly oriented element.] using $\sigma_x = 5.5 \text{ MPa}$, $\sigma_y = 4 \text{ MPa}$, and $\tau_{xy} = 3.2 \text{ MPa}$.