【简答题】如图所示,质量为 M 、倾角为 α 的斜面体 ( 斜面光滑且足够长 ) 放在粗糙的水平地面上,底部与地面的动摩擦因数为 μ ,斜面顶端与劲度系 数为 k 、自然长度为 L 的轻质弹簧相连,弹簧的另一端连接着质量为 m 的物块.压缩弹簧使其长度为3/4 L 时将物块由静止开始释放,且物块在以后的运动中,斜面体始终处于静 止状态.为 g . (1) 求物块处于平衡位置时弹簧的长度; (2) ...
【简答题】I Was Hoping I Could Just Talk to Him. Watch the following dialogue,paying attention to the underlined parts,and then role-play it with your partner. Driver: Excuse me, officers. 1 was wondering if yo...