【简答题】在图所示平面系统中,已知:匀质圆盘A和匀质圆环B均重P,半径均为R,两者用杆AB相连,若均沿倾角为φ的斜面作纯滚动,略去杆AB重量,试求: (1)杆AB的加速度;(2)杆AB的内力;(3)轮A受到的摩擦力。
【多选题】blue / remembered the /she / at her grandmother’s home / small / statue .
D.
at her grandmother’s home
【单选题】-----Hello, come in. . -----Thank you.
【单选题】—_______? —She's staying at home. [ ]
B.
What is she doing this weekend
D.
How long is Lily staying at home
【单选题】---She’s seldom asked to do housework at home, she? --- . Her parents are very busy with their work, so she has to do the laundry every day.
【简答题】在图示的平面系统中,匀质球A重为P,借本身重量和摩擦不计的理想滑轮C 和柔绳维持在仰角是α的光滑斜面上,绳的一端挂着重为Q 的物体B。试分析物体B、球A 和滑轮C 的受力情况,并分别画出平衡时各物体的受力图。
【单选题】发酵工程以培养微生物为主,所以又称为()
【简答题】在图所示系统中,已知:匀质圆柱A质量为M、半径为r,小球B质量为m,绳AB长为b,圆柱A沿水平面作纯滚动,滑轮质量忽略不计。试以x和φ为广义坐标,用拉氏方程建立系统的运动微分方程。