How does the capillary effect depend on the length of the tube?

The capillary effect in the liquid arises at the boundary of two media, moisture and gas. It leads to a curvature of the surface, making it concave or convex.

Capillary effect of water

When the vessel is filled with H ₂ O, its surface is even. However, the walls are bent. If they are wetted, the surface becomes concave, if they are dry - curved. The attraction of H2O molecules to the walls of the vessel is greater than to each other. This explains the capillary effect. The force raises the molecules H ₂ O until the hydrostatic pressure balances it.

Observations

In the framework of the experiments, the researchers tried to determine how the capillary effect depends on the length of the tube. In the course of observations, it was revealed that it does not depend on the length of the tube, the thickness of the vessel is important. In narrow spaces the distance between the walls is small. As a result of the curvature, they are connected to each other. The capillary effect is also summarized. Accordingly, the level of H ₂ O in a thin vessel can be higher than in a wide vessel.

Priming

In any soil there are pores. They also have a capillary effect. Pores are the same vessels, only very small ones. In all the soils it is observed to some extent.

The rise of H2O molecules occurs despite the force of gravity. The height of the elevation depends on the type of soil. On clay soils, it can be up to 1.5 m, and on sandy soils it can be up to 30 cm. This difference is related to the pore size. In sandy soils, they are very large, respectively, capillary force is small. Clay particles have a smaller size. Hence, the pores in the ground are less, and the effect is stronger.

Practical moments

Capillary effect in soil should be taken into account when designing and laying the foundation. As was said above, in the clay soil, moisture can rise by 1.5 m. If the foundation is laid below this mark, it will always be in the water. This, in turn, will negatively affect its bearing capacity. To protect the foundation from moisture, a waterproofing gasket is necessary.

Concrete

This material is used in the construction of the foundation. In concrete, as in the ground, a capillary effect is also possible, because this material has a porous structure. In the pores of moisture spreads deep and up.

If the foot of the basement rests on a wet ground, the water will rise, reach the base and go higher. This can lead to the destruction of all structures. To prevent such consequences, the waterproofing is laid between the ground and the basement foundation, the socle and the walls of the house.

Ultrasonic capillary effect

This phenomenon was discovered by Academician Konovalov. The scientist performed a fairly simple experiment. To the radiator generator he attached a vessel with water, dropping a capillary tube into it. According to natural laws, the force began to affect H ₂ O, causing it to rise to a certain level. After switching on the ultrasonic generator, the water made a sharp jerk upward. This experience the academician repeated, adding a dye to the vessel. After the generator was turned on, clearly visible in the tube were rarefactions and nodes of standing waves.

conclusions

Academician Konovalov established that if the water in the capillary oscillates under the influence of an ultrasonic source, then the effect of raising its level increases sharply. The height of the column becomes more sometimes several dozen times. At the same time, the rate of ascent also increases.

The scientist was able to prove experimentally that the liquid is pushed not by capillary forces and radiation pressure, but by standing waves. Ultrasound constantly compresses the post and raises it. The process will continue until the pressure produced by the waves is balanced by the liquid level.

Application

The ultrasonic effect is used in non-destructive control verification methods for the release of semiconductor equipment. In earlier times, to check the tightness of the transistor case, the device was placed for three days in an acetone bath. Using ultrasound can significantly reduce the time to 3-9 minutes. The opening of Konovalov is used when impregnating the windings of electric motors with insulating compounds, when painting fabrics - wherever moisture penetration into the pores is required.

Effect of vibration

In the process of cutting metals, especially at high speeds, lubricating coolants are used . Due to them, the friction is reduced, the temperature of the tool is reduced, and its wear resistance is increased. It is known that the liquid can penetrate the chisel. How does this happen if it is pressed tightly against the part at a pressure of up to 200 kg / cm², and under these conditions the lubricant should be forced out from under the cutter?

It was not possible to explain this phenomenon by the capillary effect. First of all, the strength and speed of lifting moisture is very small. In addition, they are caused by surface tension. The height of the lift is significantly reduced when the temperature rises, which can reach up to 300 ° C in the cutting zone. Konovalov managed to prove that, apart from the capillary effect, the vibration is affected by the machine. It occurs during the processing of the workpiece. This vibration has a higher frequency and a small amplitude.

Explanation of some phenomena

For a long time scientists failed to explain the flowering of the royal primrose before the earthquake. The flower it grows on about. Java. And the locals consider him a fortune teller. According to Konovalov, the powerful tremors of the cortex are preceded by insignificant different-frequency, ultrasonic, including oscillations. They promote the acceleration of the movement of nutrient compounds across plant elements, activate metabolic processes, which ensures flowering.

Conclusion

As you can see, the capillary effect is one of the most widespread natural phenomena. Stems, leaves, trunk, branches of different plants are permeated with a huge number of canals. On them to all organs nutrient connections are delivered. Capillary effect is used in a variety of spheres of human activity: from the resinization of sleepers and the creation of special ceramic products impregnated with molten metals, before pickling the cucumbers.