고체역학 (Beer) — Principal Stresses Under a Given Loading: Problem 8.28

8.28 Assuming that shaft \(ABC\) of Prob. 8.27 is hollow and has an outer diameter of \(50 \text{ mm}\), determine the largest permissible inner diameter of the shaft. (Prob. 8.27: The solid shaft \(ABC\) and the gears shown are used to transmit \(10 \text{ kW}\) from the motor \(M\) to a machine tool connected to gear \(D\). Knowing that the motor rotates at \(240 \text{ rpm}\) and that \(\tau_{\text{all}} = 60 \text{ MPa}\), determine the smallest permissible diameter of shaft \(ABC\).)