[填空题]
A small 650-gram balbrfrjz ga )t7.* .pu+nl on the end of a thin, light rod +,6gvu/mpzlo is rotated in a horizontal circle of radius 1.2 m.,pz o6v/ lg+mu Calculate (a) the moment of inertia of the ball about the center of the circle, $kg \cdot m^2$ (b) the torque needed to keep the ball rotating at constant angular velocity if air resistance exerts a force of 0.020 N on the ball. Ignore the rod’s moment of inertia and air resistance. $m \cdot N$
Post time 2025-2-18 20:00:22
