作为轴上各点共性的对轴的角动量定理

Theorem of Angular Momentum for Fixed Axis Rotation

角动量、力矩等用矢量表示的物理量是对指定的某个参考点定义的.而它们在某一轴上的投影所表示的物理量却属于轴上各点的共同性质.用这样的观点,重新推导和认识了绕定轴转动的刚体的角动量定理.

Some vectorial physical quantities, like angular momentum, torque, are defined with respect to a given reference point. However, the components of these vectorial physical quantities along an axis express common character belonging to all points on the axis. Based on this viewpoint, the theorem of angular momentum for a rigid body rotating about a fixed axis is deduced and realized anew.