[问答题]
Two blocks, each of mass m, etmz74/yqa7s:ow-j i(3cwc c are attached to the ends of a masslessy:p6m7pd7 f665vxjgay 0o z (s)jw npu rod which pivots as shown in Fig. 8–40. Initially the rod is held in the horizontal position and then released. Calculate the magnitude and directions6m7 y opyj)j vz7a0xp f5(p6:wd6g nu of the net torque on this system.