[填空题]
(a) A yo-yo is made of bas4(/ (bv ynal f -z )mq,6y+sbdk0cgtwo solid cylindrical disks, gln6qsb 3d71u7qz 2(r g +vq9jcd.ozr each of mass 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 r3oq+7q(srjv.2z9gb dngz 1qc du 67lenergy 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? %