应用KPK力学方法研究落体的运动

Analysis on the falling motion with KPK mechanics method

利用动量流强度,分析了在阻尼介质中的物体包括高空跳伞运动员的运动规律。首先介绍了德国卡尔斯鲁厄物理教程的力学体系,该体系将动量和速度定为力学的中心物理量,根据力的定义式与电流的定义式的类比把力看成动量流强度,利用动量的连续性方程来解决力学问题。接着运用卡尔斯鲁厄物理教程的力学方法计算了物体在空气中下落时速度变化规律,继而定性地分析了具有水平运动速度的高空跳伞运动员在达到第一收尾速率之前会有一个极小速率的原因,说明卡尔斯鲁厄物理教程的力学体系解决力学问题不仅是可行的,而且是有效的,更能让人们在新的高度认识物理学。

Making use of the concept momentum current intensity,the motion of objects including the falling of skydivers in damping medium was analyzed.The mechanics system of Der Karlsruher Physikkurs was introduced,where momentum and velocity were regarded as the central physical quantities.According to the definition analogy between force and current,the force was regarded as the momentum current strength.Mechanical problems was solved according to the continuity equation of momentum.The speed of the object falling in the air was calculated using this method and the reason for the existence of a minimum velocity for the skydiver with horizontal velocity before reaching the first closing speed was qualitatively analyzed.The study shows that the mechanics system of Der Karlsruher Physikkurs is not only feasible,but also effective.This can make people understand physics at a new height.