[问答题]
Two blocks, each of mass m, are attached to thrkfq o7n(qv r+g35w-hp4 s su2emh1 l4-mdjfcg 46h .:.ogs mjg ends of a massless rod which pivots as shown in Fig. 8–40. Initially the rod is held in the horizontal position and then released. Calculate6ghj dho:ml-smjf. g.4c1 g 4m the magnitude and direction of the net torque on this system.