[填空题]
A potter is shaping a bowl on a potter’s wheel rot8;p. 27 z ku,fkqdurp6dulot3ating at constant angular jir/,dwf)-ovw:v;k ;zt1c.1(cg wliyt ,v tg speed (Fig. 8–42). The friction force between her hands and lz-;g( itfr/g.w;c1jd,tw)vvk, 1y :wvoic tthe 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