일반물리학 1 — Rolling, Torque, and Angular Momentum: Problem 37

37 In Fig. 11-38, three particles of mass \(m = 23\text{ g}\) are fastened to three rods of length \(d = 12\text{ cm}\) and negligible mass. The rigid assembly rotates around point \(O\) at the angular speed \(\omega = 0.85\text{ rad/s}\). About \(O\), what are (a) the rotational inertia of the assembly, (b) the magnitude of the angular momentum of the middle particle, and (c) the magnitude of the angular momentum of the assembly?