[问答题]
A large spool of rope rolls o/9 gi.tf t/5ppa) capan the ground p2q;4k rekj u5with the end of the rope lying on the top edge of the spool. A person grabs the end of the rope and walks a distance L, holding onto it, Fig. 8–50. ;erupqj52 4kkThe spool rolls behind the person without slipping. What length of rope unwinds from the spool? How far does the spool’s center of mass move?