用轻绳相联系的“两体”是高中物理常见的一种理想模型,这一类“两体”问题经常会涉及到“轻绳末端速度”的分解,这是高中物理教学中一个难点.很多资料在介绍速度分解法时,一般就明确告知学生此类问题要按运动的实际效果分解,或沿绳子方向和垂直于绳子方向分解,而没有说明为什 The “two body” associated with the light rope is an ideal model common in high school physics. The problem of “two body” in this category often involves the decomposition of “the speed of the end of a light rope”, which is a difficult point in high school physics teaching. A lot of information in the introduction of speed decomposition method, generally explicitly inform the students that such problems should be broken down according to the actual effect of the movement, or along the direction of the rope and perpendicular to the direction of the rope decomposition, but did not explain why