[填空题]
(a) A yo-yo is made of two sol mi06gk g 942drp(zayzw1 zn/iid cyliu1r bwz )z 5) knq2eef8pu9)bxndrical disks, each of mass 0.050 kg and diameter 0.075 m, joined by a (concentriq 2)9 efz1pbk)8)uezrwu5 nbx c) 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 from rest. $m/s$ (b) What fraction of its kinetic energy is rotational? %