静态摩擦和动态摩擦之间的差异

Static friction vs Kinetic friction

静态摩擦和动态摩擦是两种形式的摩擦形式。当涉及固体机制领域时，摩擦是一个非常重要的概念。摩擦被认为是机械能量损失的主要原因之一。因此，为了节省能源而开发更有效的机械，必须对摩擦进行良好的理解。摩擦，无论是静态的还是动力学，在我们的日常生活中都起着至关重要的作用。如果不是摩擦，我们根本就无法走路甚至抓住勺子。理解摩擦在机械工程，汽车工程，物理甚至生命科学等领域非常重要。在本文中，我们将讨论什么是静态摩擦和动力学摩擦，它们的定义，如何发生，相似性，哪些因素影响静态和动力学摩擦以及最终的差异。

Static Friction

To understand what static friction is one must first understand the concept of friction as a whole. Friction can occur in any medium. It is the resistance of the media to a relatively moving object, or an object that is attempting to move. Static friction is a sub section of dry friction. When two solid objects touch each other, there is a force resisting the relative movement of the two faces. The main cause for this resistance is the unevenness of the two faces. These faces have little peaks on the microscopic level. When peaks of one surface go into the valleys of the other surface, these objects tend to lock, restricting the relative motion. If an object placed on a flat surface is given a force parallel to the plane, the object will not move. This is due to the static friction. By the principle of force equilibrium, the static friction is equal to the force applied. Dry friction has three main laws. Amonton’s first law says the force of friction is directly proportional to the load applied. Amonton’s second law says the force of friction is independent of the contact area. The third law considers kinetic friction. It can be formulated that the force of friction is equal to the normal force to the surface times the proportionality constant. However, since friction is equal to the applied force the proportionality constant varies with the applied force, this proportionality constant is known as the coefficient of friction. There is a maximum value for the static friction, and therefore, it is the static frictional coefficient. A force, which is greater than the maximum force of friction, is required to move the object.

Kinetic Friction

Kinetic friction occurs when two touched object move relative to each other. The coulomb’s law says that the kinetic friction is independent of the sliding velocity. It is observed that the kinetic friction is little lower than the maximum static friction. This causes the imbalance feeling when an object starts to move. The kinetic friction on each surface is always opposite to the direction of movement.

What is the difference between Static Friction and Kinetic Friction? •当两个对象相互静止时，就会发生静态摩擦，但是当两个对方相互移动时，动力学摩擦就会发生。 • Kinetic friction is less than the maximum static friction. •静态摩擦可能为零，而动力学摩擦则不能如此。