[填空题]
(a) A yo-yo is made of two solid cylindricatr)l-z 5(..m bnwv mqn;j9i dql disks, each of mass 0.050bfm bwc/o)a d6p 5k px)-jrg./ 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-y6wf-bxd k.)p)oprmgbj / ac5/o 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? %