申論題

Problem 4 (25%)
A stepped shaft ACB is held against rotation at ends A and B and subjected to a torque T₀ acting at section C. The two segments of the shaft have diameters d_A and d_B, respectively, and polar moments of inertia I_pA and I_pB, respectively. The shaft has length L and segment AC has length a. For what ratio a/L will the maximum shear stresses be the same in both segments of the shaft?