[填空题]
(a) A yo-yo is made ix86nan0lexb33m d4s89c apq of two solid cylindrical disks, each of ma **zr6)fru0 in izuas8ss 0.050 kg and diameter 0.075 m, joined by a (concentric) thin solid cylindrical hub of mass 0.0050 kg and diameter 0.010 m. Use conservation ru* i6nrzf0 suai8z*)of energy to calculate the linear speed of the yo-yo when it reaches the end of its 1.0-m-long string, if it is released from rest. $m/s$
(b) What fraction of its kinetic energy is rotational? %