What is friction in physics?

What is friction? What is the significance of this physical quantity? In the world around you, there are many interesting physical phenomena: lightning, snow, hail, thunder. And what is friction? Let us analyze the features of this process, the field of its application.

Examples of origin

If you run up, you can ride on an ice path for a certain length. On the asphalt surface, such a situation is impossible. What is the reason for this difference? Determines this difference in friction. Physics thoroughly examines all the causes of the emergence of this force.

Characteristic

The frictional force of motion occurs when two bodies come into contact. One of them will interfere with the movement of the second, this force is the force of friction. There are several variants of such forces that arise under certain conditions.

Types of friction

If it is necessary to move a heavy closet from a place, it is rather problematic to do this to one person. It is necessary to increase the "shearing" force. In this case, the frictional force of rest will also increase. Its direction is opposite to the movement of the moving cabinet.

At the moment when the traction force acquires a value greater than the friction of rest, the cabinet changes its location. At that moment another friction force appears. Acceleration, which is the friction of motion, determines the nature of the movement. If it prevails over the pulling force, then it will be difficult to talk about rapid movement.

Sometimes on the roads there are situations in which several people try to move a stalled vehicle. During the pushing of the car they use the frictional force of the rolling. Acceleration occurs during the rolling of the body along the road surface.

The coefficient of friction in this case depends on the pattern on the tires, the condition of the roadway, weather conditions.

If a round ball moves along the surface, the friction is negligible. This phenomenon is widely used in everyday life. Massive furniture is equipped with special wheels, allowing (if necessary) to move it from one section of the room to another.

Features of strength

What is friction? It is a force directed opposite to the movement of the body. This physical value helps to reduce the speed of the body. If there was no such force, you could move around on rollers or a bicycle without making any effort. It is the existence of the frictional force that explains the movement of the vehicle a certain distance after the engine has been muffled. The main types of friction are: rolling, sliding, rest.

The nature of friction

Arguing over what such friction is, it is necessary to reveal the nature of the origin of a given force. In the presence of a smooth surface, such as ice or polished table, you can see minor roughness only with a magnifying glass or microscope. It is for them to "cling" the body, moving on the surface. Since certain irregularities exist in the moving object itself, there is a contact between the surfaces.

At first, the bodies are attracted to each other, but as the moving object moves away, the clutch collapses. As a result, oscillation of atoms released from mutual attraction occurs. Similarly, the state of the stretch spring can be described.

During friction, an increase in temperature is observed, that is, a certain amount of heat is released.

The causes of friction

A given force arises when there are unevennesses on the contact surface of two bodies, and also because of the strength of the intermolecular interaction.

Depends on the frictional force of the material from which the contiguous surfaces are made, the weight of the interacting objects. For the mathematical calculation of a given physical quantity, there is a special formula relating the frictional force to the force acting on the support, and also with the coefficient of friction.

It reflects the dependence of the magnitude of the desired force on the selected material, and also on the quality of its processing. The unit of reaction of the support when the body moves along a horizontal surface is equal to its weight. In the case of an inclined plane, its value decreases, so from a steep mountain on skis (sledges) it is possible to take a very impressive distance.

This force does some work. If the body moves, it is imperative that the work is done. The frictional force tries to prevent the object from moving around the surface. That is why the work done by her, a negative value.

Application of friction

A person in his daily life is always accompanied by a force of friction. It can have both positive and negative effects. For example, if there was no such force in nature, the bodies would slide down, the transport would fall into separate details.

It would be difficult to tie shoelaces on shoes, to keep the interior items on a permanent place. Man in the absence of friction could not have made even one step. In order to solve a similar problem, during a hard ice, they try to sprinkle the tracks with a thick layer of sand. Increasing the surface roughness increases the frictional force, helping people without any problems to move along slippery sections of the road or sidewalk.

But in addition to the positive effect, friction often exhibits negative properties. People are able to increase and decrease its value, getting maximum benefit for themselves. For example, to move heavy loads from one place to another, use the wheels. In order to convert sliding into rolling, for example, increase the surface roughness.

Depending on what pattern was applied to the tires, they are used to move the vehicle across different sections of the road.

Rubber is black because it contains coal. It is necessary for giving tires strength, necessary rigidity, increasing friction on the road surface. If the friction force is calculated correctly, the desired result can be obtained.