[填空题]
A potter is shaping a bowl on a potter’s wheel rotatitzvccoktn6ve q u7via3 z;23), i*i-q ng at constant angular cxarph)j+ q: 9speed (Fig. 8–42). The:rha)+x 9pjqc friction force between her hands and the 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