[填空题]
(a) A yo-yo is made ovbmusq60)n6)l vs0qm( sh3 maf two solid cylindrical disks, each of m .4fha1-o at,tv v/rsmass 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 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 from1-/aorasfhv vt .,4mt rest. $m/s$ (b) What fraction of its kinetic energy is rotational? %