[填空题]
A cyclist accelerates fromz.9 -0g qeyhnb*4 gwgt rest at a xy/ k+h0v*zrvjrgc gcs/ ih7v6cb- 0) 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.] $m/s$