也谈惯性力的施力体与受力体

More Discussion about the Loading and Loaded Body of Inertia Force

惯性力在两种场合出现。一是在非惯性参照系下建立质点的动力学方程时需引入适当的惯性力 ;一是在用动静法解动力学问题即达朗伯原理中出现。仔细对比这两种场合出现的惯性力 ,便会发现它们是两个不同的概念 ,存在明显的差异 ,在非惯性系下建立质点的动力学方程时引入的惯性力只有受力者 ,没有施力者 ,而达朗伯原理中出现的惯性力都是物体之间的相互作用力 ,有施力者 ,有受力者。

Inertia force occurs under two different circumstances: one is when the equation of dynamics for a particle is to be built under a noninertia reference frame, the other occurs when using the method of dynamic equilibrium (d′Alembert′s principle) to solve a dynamical question. Compare these two kinds of inertia force carefully and then it will be found that they are different conceptions, between which there are obvious differences. The inertia force which occurs when equations of dynamics are to be built has loading body but no loaded body. But in the d′Alembert′s principle,all inertia forces are interactions between two objects, so they have loading body and loaded body. [WT5HZ]