In the field of physics, we first involved friction. As we all know, it is a force generated between objects. For example, in a stretching area, it needs to be acted by a * * * pulling force or pressure, so the friction force in the whole movement process is called the friction force boundary. In the area of friction distribution, the distribution of friction intensity at each point is called friction.

Friction actually exists widely in our social life. For example, when we put books on the table in class, there is friction between the table and the book. When we sit on the bench, there is also friction between our pants and our bench. If we usually lean against the wall, then there is a friction force in our human body synthesis. As long as there is a collision between two objects, there will be friction.

In the process of friction, if there is a pressure and a pulling force during the movement of an object, and you still have a maximum pulling force borne by another object, then the whole concept of a system is called the friction boundary, and the factors affecting the friction boundary are mainly related to the strength and scope of our movement.

In addition to the friction boundary, there is an additional friction boundary. Everything that rubs against each other is on a circle composed of two teams, and some control devices or artificial control factors are added to form a friction boundary. For example, under the intervention of human beings, the friction intensity is increased or the friction range is expanded and the distribution is relatively stable. Then, for an object, effective elastic control will be formed.