All objects on Earth are constantly influenced by various physical forces. One such force is friction which occurs “between two surfaces that are sliding, or trying to slide, across each other” (“What is friction?” n. d.). This force is always directed against the course of movement of the object. Thus, friction resists the moving of the object and always reduces its speed. This force can only occur when two surfaces are in relative motion and affect each other. Friction can be beneficial or undesirable depending on the situation.
Although this force occurs with any movement, sometimes its effect is intentionally increased or decreased. Friction can help when one needs to reduce the speed of an object or stop it. For example, when landing aircraft, the friction between the wheels and the runway is used as additional braking force. Jet planes even have a special parachute which further increases the friction between the surface and the atmosphere. However, when an object’s movement of an object is to be accelerated, the effect of frictional force should be minimized. For example, the occurrence of this force between the moving elements of mechanisms, in particular cars, is undesirable since it produces heat and wears on the parts.
The appearance and nature of friction are influenced by many factors, including surface texture, temperature, moving speed, object weight, and lubrication. Thus, manipulations with these features are used to increase or eliminate the force (“How to reduce friction,” n. d.). Primarily, rolling causes much less friction than sliding due to the reduced volume of surface interaction. Thus, the use of wheels is the most effective means of reducing the effect of this force. Materials with a more smooth texture should be used since the size of microscopic fractions affects the occurrence of friction. A lubricant such as oil creates a layer between surfaces, which also helps to reduce friction. Reducing the influence of normal force, which means placing the object as parallel to the motion surface as possible, also minimizes force.
Accordingly, opposite methods should be applied to increase the impact of this force. First of all, increasing the normal force, that is, the object’s perpendicular position relative to the surface, increases friction (“How we can increase friction?” 2020). Removing any type of lubrication also allows the surfaces to interact with each other. Finally, using sliding instead of rolling increases friction by expanding the surface area.
How to reduce friction between surfaces. (n. d.). Machinery Lubrication.
What is friction? (n. d.). BBC.