The conservation of momentum and kinetic energy under the condition of a perfectly elastic collision is a well-known common sense, but the analysis and research data on its internal factors are not common, so this paper will explore and discuss it. I hope that interested friends will give more comments and suggestions.According to the general law that the change of the state of motion of matter with mass must be the result of the action of force, we can naturally think that the law of conservation of momentum and kinetic energy under the condition of a completely elastic collision should be the interaction between two colliding objects. Determined by the action force: when two objects collide with each other, the contact surface is simultaneously subjected to an action force and a reaction force of equal magnitude but opposite directions, so that each other quickly reduces the speed of motion and changes the speed and direction of motion. We assume that the interaction force during the collision does not change with time, then the force of the collision has exactly the same start and end time of the variable speed motion imposed by the collision, and the collision will first decelerate and then accelerate. Of course, there is no transfer of so-called momentum or energy in this process.

完全弹性碰撞条件下的动量和动能守恒是广为共知的常识，但就其内在因素的分析与研究资料并不常见，本文就此进行一些探索与讨论。希望有兴趣的朋友们多提意见与建议。按照有质量物质运动状态的改变必定是力的作用之结果的普遍规律，我们可以很自然地想到：完全弹性碰撞条件下的动量和动能守恒定律应该是两个碰撞物体间相互碰撞时产生的相互作用力决定的：当两个物体相互碰撞时，接触面同时受到大小相等但方向相反的作用力与反作用力使彼此快速降低运动速度并改变运动速度与方向。我们假设碰撞过程中的相互作用力不随时间变化，则碰撞的作用力对碰撞双方所施加的变速运动的开始与结束时间完全一致，碰撞会使双方先减速后加速。此过程当然不存在所谓的动量或能量的传递。