The strength of the wind resistance - and without in any way

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We are so accustomed to being surrounded by air, which often do not pay attention to it.The point here is, above all, the application of technical problems, the solution of which at first forgotten that there is a force of air resistance.

It reminds himself almost any action.Though we will go by car, though flying a plane, even if we just throw a stone.So try to understand what the force of air resistance on the example of simple cases.

you wondered why cars have a streamlined shape and a flat surface?But it's actually very clear.The strength of the resistance of the air is composed of two variables - the frictional resistance of the surface of the body and the shape of the body resistance.In order to reduce the frictional force and achieve reduction of roughness and irregularities at the outer parts in the manufacture of vehicles and any other vehicles.

them primed for this, stained, polished and lacquered.Such processing components leads to the fact that the air resistance acting on the vehicle is reduced, the vehicle speed is increased and fuel consumption is reduced when driving.The presence of the forces of resistance is due to the fact that when the vehicle is moving and the air is compressed before it creates a local region of high pressure, followed by, respectively, the area of ​​the vacuum.

should be noted that at high speeds the car a major contribution to the resistance makes the shape of cars.The strength of the resistance calculation formula is shown below, determines the factors on which it depends.

resistance force = Cx * S * V2 * r / 2

where S - area of ​​the front projection machines;

Cx - coefficient taking into account the aerodynamic drag;

V - speed of movement;

r - the density of air.

It is easy to see from the above formula, the resistance force is independent of the weight of the car.The main contribution is made of two components - the square of the speed and shape of the car.Ieat higher speed twice to four times to increase the resistance.Well, the cross-section of the vehicle has a significant impact.The car will be more streamlined, the less air resistance.

and claims there is still the option that simply requires him to pay attention to - the density of air.But its effects are more noticeable when flying aircraft.It is known that with increasing altitude the air density decreases.So therefore it will diminish the strength of his resistance.However, for the value of the aircraft to resist will continue to affect the same factors - speed and form.

No less curious is the history of the study of the effect of air on the accuracy.Work of this nature for a long time were the first descriptions relate to 1742.The experiments were conducted in different countries, with different forms of bullets and shells.As a result, research has determined the optimal form of bullets and the ratio of its head and tail parts of the table are designed ballistic behavior of bullets in flight.

Later studies were conducted according to a bullet from her speed, continued to be practiced form of bullets, as well as improved methods of research.There have been developed mathematical model and a special mathematical tool - ballistic coefficient.It shows the correlation of forces of aerodynamic drag and inertia forces acting on the bullet.

The article discussed what constitutes the force of air resistance, given a formula that allows to determine the magnitude and extent of the influence of various factors on the resistance value, consider its impact in different areas of technology.