[问答题]
Two blocks, each of maw,d n r5c 84i0rrqi7oiss m, are attached to the ends of a massl;8osw sg- )usa5jphyov- /lh (ess rod which pivots as shown in Fig. 8–40. Initially the rod is held in the horizontal position and then rv5- w)hs opy8/aos;gs -huj(leleased. Calculate the magnitude and direction of the net torque on this system.