Gere & Goodno — Applications of Plane Stress: Problem 8.4-3

8.4-3 A simply supported beam is subjected to two point loads, each \(P = 2.25 \text{ kN}\), as shown in the figure. The beam has a cross section of \(150 \text{ mm} \times 300 \text{ mm}\). Find the state of plane stress at point \(C\) located \(200 \text{ mm}\) below the top of the beam and \(160 \text{ mm}\) to the right of support \(A\). Also find the principal stresses and the maximum shear stress at \(C\).