The difference between ultrasound and secondary waves, is ultrasound and infrasound a contradictory

The vibration frequency is different, the characteristics are different, the hazards are different, etc.

1. The vibration frequency is different.

Ultrasound is a type of ultrasound with a frequency higher than 20,000 Hz; Secondary waves are frequencies less than 20 Hz (Hertz). Ultrasound gets its name from the fact that the lower limit of its frequency is greater than the upper limit of a person's hearing. Ultrasonic has good directionality, strong penetrating ability, easy to obtain concentrated sound energy, and has a long propagation distance in water, which can be used for distance measurement, speed measurement, cleaning, welding, stone crushing, sterilization and disinfection, etc.

2. The characteristics are different.

Infrasound waves are characterized by wide spread, long propagation, and the ability to travel far away around obstacles; Ultrasonic waves are characterized by strong directionality and easy concentration of energy when propagating.

3. The hazards are different.

Infrasound waves can interfere with the normal function of the human nervous system and endanger human health; Ultrasound is good for people. Infrasound waves of a certain intensity can make people dizzy, nauseous, vomiting, loss of balance and even mental depression. Stronger infrasound waves can also cause deafness, coma, insanity, and even death.

Ultrasound is a form of wave, which can be used as a carrier or medium for detecting and loading information, such as B-ultrasound, etc., for diagnosis; Ultrasonic wave is also a form of energy, when its intensity exceeds a certain value, it can be used to influence, change and destroy the state, properties and structure of the latter through interaction with the medium that transmits ultrasound.

Encyclopedia - Infrasound.

Encyclopedia - Ultrasound.

The main difference between ultrasonic waves and secondary waves is: vibrational frequency.

Let's start by understanding what sound waves are, which are the form of propagation of the state (or energy) of an object's mechanical vibration. Vibration refers to the reciprocating motion of a particle of matter near its equilibrium position.

For example, when the drum is struck, it vibrates up and down, and this vibrational state travels in all directions through the air medium, which is called sound waves (in general, sound waves that can be heard and felt by people in the natural environment are called sound waves).

When the vibration frequency is higher than 20kHz (or the vibration frequency is greater than 16Hz), the sound waves that cannot be heard and felt by people in the natural environment are called ultrasonic. People usually call sound waves with vibration frequencies greater than 16 Hz as subultrasonic waves (referred to as infrasound), and vibration frequencies greater than 20kHz are called ultrasounds.

A simple and clear sentence:

Ultrasound waves are often used by people, while secondary waves are often annoying and not beneficial

Ultrasound andInfrasoundIt's not a contradiction, it's a juxtaposition.

The frequency of sound waves that people can hear is between 20 and 20000Hz, the frequency higher than 20000Hz is "ultrasound", and the frequency below 20Hz is called "infrasound", and the two belong to a juxtaposition relationship. Ultrasound and infrasound are both sound waves, which are used in today's clinical medicine.

, the applications are relatively wide.

With the gradual development of medical aesthetic technology, ultrasound and infrasound have gradually been applied to the medical aesthetic industry, helping people solve a variety of image problems and making people more beautiful.

Features of ultrasound:

1. When ultrasonic waves are propagating, the wavelength is short and anisotropic.

2. Ultrasonic waves can propagate in a variety of different media, and can propagate long enough.

3. The interaction between ultrasound and the sound medium is moderate, and it is easy to carry information about the state of the sound medium to diagnose or have an effect on the sound medium.

4. Ultrasonic waves can be effectively propagated in gases, liquids, solids, solid melts and other media.

5. Ultrasonic waves will produce reflection, interference and superposition.

In fact, these two concepts are for human hearing. Ultrasonic refers to sound waves with a high frequency, and to put it bluntly, they are sound waves with a high number of vibrations per unit of time. Infrasound, on the other hand, is a sound wave with a very small frequency.

It is also a sound wave that vibrates very little per unit of time. Let's put it this way, for example, all sound waves have the same velocity. So let's assume that two people run, one person is tall and has longer legs, and the other person is short and has shorter legs.

Run a certain distance and reach the finish line at the same time. (Assuming that the weight of the two is the same) so which of the two does the most work in this process? Let's say a tall person runs 10 steps and a short person runs 15 steps.

Then every step they take in contact with the ground is subjected to a frictional force. According to the theory of fs, because the gravity is the same and the friction factor is the same, the friction f is the same, so whose s is longer? That is, whose friction lasts a long time?

Obviously, the person who ran 15 steps, that is, the frequency, then this person needs to consume more energy. Similarly, ultrasound carries more energy than infrasound. Again, in this example, if there is a step in the distance that the two people are running, then whoever has a certain step is exactly the same as the step is likely to be larger.

If it is not clear, if the person who runs 15 steps is changed to 100 steps, then the effect of the steps on him will be less, because there is a high probability that he will go to the bottom of the steps and then go up the next step. But the 10-step one, it may also be exactly at the bottom of the steps, and then go up one step, but it is more likely that he has to adjust this step. In other words, infrasound is more limited by the terrain, that is, by the shape.

In the same way: the dish is washed with ultrasound because it has a large energy and can have the molecular force between the oil and the plate. And because it is less affected by the shape, there is no place where it cannot be washed.

Sonar, which is basically the same factor, is mainly energy and shape. I don't know if I can understand this.,The examples are now found.,Maybe some places are not so perfect.,But the general meaning.,But that's how I understand it.。