摘要
刚体定轴转动的打击中心是一个很重要的力学概念,但在很多《大学物理》教材中都没有介绍.本文以一根质量均匀分布的细杆绕端点作定轴转动为例,首先从动力学的角度,分析刚体的受力和力矩,根据动力学方程,分别计算出打击中心位置;然后从运动学角度出发,以转轴O点的切向速度和切向加速度等于零为条件,再分别寻找打击中心的位置.计算结果表明:上述4种方法得出的刚体打击中心位置是相同的.最后简介刚体打击中心在体育运动、日常生活中一些应用.
The center of percussion of rigid body rotating about a fixed axis is an important mechanical concept, but it is not introduced in many ＂Collage Physics＂ books. In this paper, we take a thin uniform rod rotating around a fixed end as an example. Firstly we calculate the center of percussion of the rod from the force＇s and torque＇s dynamical equation respectively; then we search the center of percussion of the rod from kinematical condition that the tangential speed and tangential acceleration of the rod＇s fixed point O are zero. The computing resuits indicate that the enter of percussion of the rod are same from above four methods. Final- ly it is introduced that some applications of center of percussion in sports and daily life.
出处
《物理与工程》
2015年第2期81-83,共3页
Physics and Engineering
关键词
刚体
定轴转动
打击中心
rigid body
rotation about a fixed axis
center of percussion
