[填空题]
A cyclist accelerates froi + gaa7xwbbsk7:ci6*meeiipb*r)4ss x nwms *o3n/7+ rest 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.] $m/s$