고체역학 (Gere) — Torsion: Problem 3.4-9

3.4-9 Four gears are attached to a circular shaft and transmit the torques shown in the figure. The allowable shear stress in the shaft is 70 MPa. (a) What is the required diameter d of the shaft if it has a solid cross section? (b) What is the required outside diameter d if the shaft is hollow with an inside diameter of 40 mm? [Data from figure 3.4-9 on page 368]: - Torque at A: \(T_A = 900 \text{ N}\cdot\text{m}\) - Torque at B: \(T_B = 2100 \text{ N}\cdot\text{m}\) - Torque at C: \(T_C = 450 \text{ N}\cdot\text{m}\) - Torque at D: \(T_D = 750 \text{ N}\cdot\text{m}\)