[填空题]
A potter is shaping a bowl on9 z7j:6k;d6xpch iaqw a potter’uh ij*yw cfw 7 -4eetdx0:t2o6s wheel rotating at constant angular speed (Fig. 8–42). The friction force between her hands and the clay is 1.5 N tota-2xj wu *o 74f6iyt ed0ew:chtl. (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