What is friction, and how does it play an important role in our daily lives and in industry?

Friction is the force exerted by two objects in contact with each other that impedes their motion. It can be divided into static friction and kinetic friction, and it plays an important role in many areas, such as the grip between car tires and the road and the design of sports shoes. Understanding and utilizing friction can make our lives safer and more convenient.

 

Friction is a force that is present almost every moment of our lives. Whether you’re walking down the street, using a pencil, or even buying something, you have to deal with friction. In this article, we’ll explain in detail what exactly this force is and what its characteristics are.
First of all, the definition of friction, which varies from person to person, is the horizontal force exerted by two objects in contact on each other. It’s hard to say, but the easiest way to put it is as it’s often written in dictionaries: friction is a force that impedes the motion of an object. When textbooks first introduce students to friction, they usually use a box as an example. If you push a box and then release it, it will stop. The reason it stops is because of the force of friction. When you try to push a box that is stopped, it takes effort because there is friction, a force that prevents the box from moving.
However, the reason why I didn’t define friction in the dictionary at first is that friction is not the only force that impedes the motion of an object. When playing with a balloon, it’s easy to see that no matter how hard you push it, it will stop, meaning there is a force that prevents it from moving. It’s not friction, it’s the resistance of the air. Also, if you push down on a desk, it doesn’t move down, even though you’re clearly pushing down. This means that there is a force preventing the desk from moving downward, and this force is called normal drag, not friction. So I define friction by emphasizing how it differs from resistance and normal drag. The first difference is that friction is a force exerted by two bodies on each other, and the two bodies must be solids. Resistance is the force exerted by a liquid or gas on an object in it. Second, friction is different from normal force in that it is exerted in the horizontal direction of a plane. Normal force is literally a force in the vertical direction of a surface.

 

 

One of the important characteristics of friction is the coefficient of friction. The coefficient of friction depends on the material and state of two objects, and is divided into static friction coefficient and kinetic friction coefficient. The coefficient of static friction is a measure of the friction force when the objects are at rest, while the coefficient of kinetic friction is a measure of the friction force when the objects are in motion. In general, the coefficient of static friction is larger than the coefficient of kinetic friction, so more force is required when an object first starts moving.
There are two types of friction: static friction and kinetic friction. Static friction is literally the frictional force that exists when an object is at rest and has the same magnitude in the exact opposite direction of the external force. Kinetic friction is literally the friction that occurs when an object is in motion and is proportional to the normal drag, which is a measure of how closely two surfaces are pressed together. There is no energy loss in a static friction force because the point of action of the force is not moving, but there is energy loss in a kinetic friction force because the point of action of the force is moving.
Friction plays an important role in many fields. For example, the friction between a car’s tires and the road helps a vehicle stop or change direction, and the shoes used by athletes in sporting events are designed with friction in mind. This is a very important factor that is directly related to safety, as a lack of friction can lead to slips and injuries.
Finally, we”d like to point out something that people often misunderstand. This is the friction force in rolling motion. When a ball or wheel rolls over a surface, it’s easy to think of it as kinetic friction because the object is in motion, but it’s actually static friction because there’s no friction between the surfaces that are in contact. Therefore, there is no energy loss in rolling motion. This can also be seen in the interaction between car tires and the road, where traction increases the grip between the tires and the road, preventing the car from sliding easily.
As you can see, friction plays a very important role in our daily lives and in many industries. Understanding and utilizing friction can make our lives safer and more convenient.