고체역학 (Beer) — Torsion: Problem 3.14

3.13 Under normal operating conditions, the electric motor exerts a torque of \(2.4\text{ kN}\cdot\text{m}\) on shaft \(AB\). Knowing that each shaft is solid, determine the maximum shearing stress in (a) shaft \(AB\), (b) shaft \(BC\), (c) shaft \(CD\). 3.14 To reduce the total mass of the assembly of Prob. 3.13, a new design is being considered in which the diameter of shaft \(BC\) will be smaller. Determine the smallest diameter of shaft \(BC\) for which the maximum value of the shearing stress in the assembly will not be increased.