【简答题】如图所示,轻弹簧的一端固定在倾角为 a 的光滑斜面的底端 E ,另一端与质量为 m 的物体 C 相连, O 点为弹簧原长处, A 点为物体 C 的平衡位置, x 0 为弹簧被压缩的长度.如果在一外力作用下,物体由 A 点沿斜面向上缓慢移动了 2 x 0 距离而到达 B 点,则该外力所作 功为 ____
【简答题】Look at the center circles of Diagram A and Diagram B. Which of the centre circles looks larger? [2] Take a first look and you probably think that the centre circle in Diagram A is smaller than that i...