【简答题】如图所示,曲柄CB以匀角速度w0绕C轴转动,其转动方程 ,通过滑块B带动摇杆OA绕O转动,设OC=h,CB=r,求摇杆的转动方程。 [2] 如图,套管 A 由绕过定滑轮 B 的绳索牵引而沿导轨上升,滑轮中心到导轨的距离为L。当绳索以等速 v0下拉时,若不计滑轮尺寸,试求套管 A 的速度和加速度(表示为 x 的函数)。
【简答题】完形填空。 Tom is six now. His mother 1 in a watch factory. She is busy all day, she has to 2 at six in the morning. Then she cooks 3 for her family. She goes to work with some 4 so she can have lunch in t...