[填空题]
A cyclist accelerates from rest at a rate ffb1of z:j(:oof 1 mj7;mb y0l, 98fqj,y pzgi0zd aw zr-1o/$s^2$ 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.] $m/s$