shuijing217
摩擦是一个特别常见但是却并不那么简单的物理现象。从初中阶段开始刚刚接触摩擦这个概念的时候，我们就知道，摩擦力的大小和正压力以及界面的粗糙程度有关系。并且定义了滑动摩擦系数的的概念，即滑动摩擦力和正压力之间的比值。但单从这个定义上来看，并没有任何限制摩擦力必须要小于正压力，原则上来说这是完全可能的。其实有个实例，轮胎在路面上的滑动摩擦系数就能接近甚至超过1。当然这个系数对于湿度非常敏感，也就是为什么雨雪天刹车距离明显边长的一个重要原因。
飞天小杨杨
I asked Detection Model are: FSDB-30, FSDB-90 and three ZSDB-120 hydraulic disc brake. The main technical parameters are as follows: FSDB-30: calipers of: 30000 N; of Power: 24000 N; friction coefficient μ = 0.4 (calculated) Unilateral withdrawal from the gate opening: 1 mm, response time: 0.2 s gate opening pressure of 80 bar; brake disc thickness: 20 ~ 40 mm; FSDB-90: calipers Force: 90000 N; of Power: 72000 N; friction coefficient μ = 0.4 (calculated) Unilateral withdrawal from the gate opening: 1 mm, response time: 0.2 s gate opening pressure of 145 bar; brake disc thickness: 25 ~ 45 mm; ZSDB-90: friction coefficient μ = 0.4 (calculated) gate opening unilateral withdrawal from: 1 mm in thickness of the brake disc: 30 ~ 40 mm; Work pressure and the corresponding dynamic system 25bar/22.5KN; 50bar/45KN; 75bar/67.5KN; 100bar/90KN; 125bar/112.5KN;
