[填空题]
A cyclist accelerates froiez-t 3 nf7 wjidg,4tde+*u:vm b;thxj w74 j:z2 shte3rest at a rate of 1 m/$s^2$ How fast will a point on the rim of the tire at the top be moving after 3.0 s? [Hint: At any moment, the lowest point on the tire is in contact with the ground and is at rest — see Fig. 8–51.] $m/s$