选择适当的参考点在解决刚体运动问题中至关重要, 能有效简化问题处理. 相对于质心转轴, 非质心系提供更为灵活的视角. 本文通过推导非质心系的角动量定理, 以小球碰撞自由杆模型为例, 展示了其在实际问题中的应用. 本文为读者提供了处理刚体运动问题的新思路, 特别是在复杂情境下更为直观. 

Choosing an appropriate reference point is crucial in solving rigid body motion problems, effectively simplifying the problem-solving process. In comparison to the center of mass axis, a non-centroid axis of rotation provides a more flexible perspective. This paper, by deriving the angular momentum theorem in a non-centroid system and using the example of a ball colliding with a free rod, illustrates its practical application in real-world scenarios. The paper offers readers a novel approach to addressing rigid body motion problems, particularly providing intuitive insights in complex situations.