Friction in our life


Sean C Crespo Gomez

With just a few introductory lectures about friction, we can see friction’s importance in our daily life. It is important to have knowledge about what is friction and how it affects us, if we have enough knowledge about friction, it can be used as an advantage in life. We can find many simple examples related to friction, as: the slippery floor when it’s wet, the oil needed to lubricate the engine and allow its parts to move easily, and when some surface is polished to shine and it does not feel rough. In some cases we need to move something heavy and we can realize that it’s much easier to roll it or somehow avoid friction between the object and the floor. That is why we need to know when we need friction in our favor, or if somehow we have to deal with the forces. We must first know the pros and cons of friction. It’s easy to note that excess friction can make it difficult to slide a box across the floor, ride a bicycle or walk through sand. We can also relate friction with the consumption of gasoline. If we deal with friction from our vehicle taking simple measures such as keeping the right amount of tire pressure, and avoiding excessive loads on the car we will see gasoline consumption remains constant and reasonable.   

    

Basically, we can define friction as the force developed between a moving body and the surface being in contact with it. An example is when you apply the brakes of a car, it’s instant friction between tires and pavement. Friction is a force that is opposite to the motion of a body on which he works. Friction is usually classified as Static friction and Dynamic (kinetic) friction. Static friction is a force which resists the lateral movement of two objects which are touching each other. In other words, static friction prevents an object to move and is equal to the net force applied to the body, but with opposite direction because it prevents the movement. When objects have a high friction coefficient it means that a large amount of force is required to break the force of static friction and create movement, while a low coefficient means that less force will be exerted. On the other hand, we have the dynamic friction (kinetic). This is when movement is involved. It’s the friction generated between two dry surfaces in contact during movement. The product is a kinetic friction coefficient of kinetic friction force and normal reaction. It assumes a constant value regardless of the amount of applied force or speed of movement. Its value is always less than the limiting friction between the same two surfaces. 

In my opinion, friction is one of the most fundamental topics in Physics due to the fact that almost every other topic is related to it. Trough this essay, I’m implying that we don’t need to be an expert on this subject, although it would be amazingly useful to cope with our daily life.