[填空题]
A potter is shaping a bowl on ne owry,29og1 a potter’s wheel rotating+jb fol;zi8 c2 at constant angular speed (Fig. 8–42). The friction force between her hands and thezl8+c; ifj2 ob clay is 1.5 N total. (a) How large is her torque on the wheel, if the diameter of the bowl is 12 cm? $m \cdot N$ (b) How long would it take for the potter’s wheel to stop if the only torque acting on it is due to the potter’s hand? The initial angular velocity of the wheel is 1.6 rev/s, and the moment of inertia of the wheel and the bowl is 0.11 $kg \cdot m^2$. s