[问答题]
A wheel of mass M has ra5zh-qdgtjxv5t ry)g d+z ; 9y0dijh 5g+ mmgc* pn(3ur-ga ;a6zwus R. It is standing vertically on the floor, and we want to exert a horizontal force F at its axle so that it will climb a step aga;mp z- *j mgg(whrn +3c6ua5aginst which it rests (Fig. 8–55). The step has height h, where h
Post time 2025-2-18 20:00:22
