What is the speed of sound in general? 20, What is the speed of sound in general?

Generally speaking, the value of the speed of sound is greater in solids than in liquids, and in liquids it is greater than in gases. The magnitude of the speed of sound also varies with the temperature of the atmosphere, and in the troposphere, as the altitude increases, the air temperature decreases and the speed of sound decreases. In the lower stratosphere[1], the air temperature does not change with altitude, and the speed of sound does not change, which is in meters and seconds.

The law of air flow and the aerodynamic characteristics of the aircraft have a qualitative difference between the flight speed being less than the speed of sound and the speed of sound, so the speed of sound is a very important benchmark value for studying the movement of aircraft in the atmosphere. The speed of sound is not a fixed value. In dry air, the empirical formula for the speed of sound is:

The speed of sound u= (c=Celsius) at room temperature (15), the speed of sound is u= , which is why it is said that the speed of sound is 340m s (1225km h). The speed of sound in moist air increases slightly, but the amplitude is less than that, and in most cases it is negligible. For Fahrenheit temperature, it can be converted using the formula:

f=9c 5+32 (c=Celsius)The international standard atmospheric ISA stipulates: in the troposphere (0 11000m), the air temperature at sea level is 15 , the air pressure is 101325Pa, the air density; For every 1000m above sea level, the temperature drops Using the above formula to calculate the temperature at different altitudes, and then combining the previous empirical formula for the speed of sound, we can calculate the speed of sound at different altitudes.

At an altitude of 11,000 to 20,000m (belonging to the stratosphere), the temperature basically does not change, so it is also called"Stratosphere"), the temperature drops to minus 57 ( here the speed of sound is u= (about 1068km h)Jets like to cruise at an altitude of about 10,000 meters because this is the bottom of the stratosphere, which can avoid the air currents generated by convective activity in the troposphere. In the stratosphere of 11,000 to 20,000 m, the standard speed of sound is 1062 km h, and it is basically stable.

The speed of sound in the air is about 1 meter at 15 standard atmospheres and 340 m s.

334 meters per second, it still has to be judged according to the temperature! You can do it yourself, there's no need to ask!

Hehe, what you think is okay, trouble plus points! Thank you.

The speed at which sound travels in different mediums of the trembling beam:

1. Vacuum 0m s (that is, it cannot be propagated);

2. Resistant to air (15) 340m s;

3. Air (25) 346m s;

4. Cork 500m s;

5. Kerosene (25) 1324m s;

6. Distilled water (25) 1497ms;

7. Seawater (25) 1531m s;

8. Copper (rod) 3750m s;

9. Marble 3810m s;

10. Aluminum (rod) 5000m s;

11. Iron (rod) 5200m s;

Finally, it is important to note that sound travels at different speeds in different substances, so when asking questions, it is important to explain clearly what Changdong rock material the sound is propagating in.

The speed of sound in the air is about 15 m seconds at 1 standard atmosphere and 340 m seconds, which is about 1224 km/h. The speed of sound is the speed of propagation of a weak pressure disturbance in a medium, and its magnitude varies depending on the nature and state of the medium.

Supersonic speed refers to the state of speed greater than 340 meters per second, and the speed less than 340 meters per second is called subsonic, which is equal to the speed of 340 meters per second as the speed of transpersonic, and the speed of sound will vary depending on the temperature or pressure. Definition of hypersonic: Speeds greater than 5 times the speed of sound are generally considered to be hypersonic.

Sound is a pressure wave: when a musical instrument is played, a door is slammed or a table is struck, their vibrations cause the medium-air molecules to vibrate rhythmically, causing the surrounding air to produce dense changes to form sparse longitudinal waves, which produce sound waves, and this phenomenon continues until the vibration disappears.

As a kind of wave, frequency and amplitude have become important properties to describe the wave, the magnitude of the frequency corresponds to what we usually call pitch, and the amplitude affects the magnitude of the sound. Sound can be broken down into superpositions of sine waves of different frequencies and intensities. This process of transformation (or decomposition) is called the Fourier transform.

Therefore, sound in general always contains a certain frequency range. The frequency range of sounds that can be heard by the human ear is between 20 and 20,000 hertz. Fluctuations above this range are called ultrasound, while those below this range are called infrasound.

Animals such as dogs and bats can hear sounds up to 160,000 hertz. Whales and elephants produce sounds with frequencies in the range of 15 to 35 Hz.