The reason why people can hear that the sound is three dimensional is because:

Everything that is making sound is vibrating, and sound is produced by the vibration of the object, so what we hear is produced by the vibration of the object

So the answer is: vibration

Answer: We can't hear ultrasound because sound is onewaves, only (frequencies) within a certain range can be for our auditory organsReceiving

The sound is due to the objectVibrationgenerated, to:Sonic wavesform passedmediumPropagation, through the human ear canal and ossicles, causes the eardrum to vibrate, and then from the auditory nerve to the auditory center of the brain, so that people can hear sound.

The human hearing frequency range is between 20Hz and 20000Hz, and infrasound waves with frequencies lower than 20Hz and ultrasound waves with frequencies higher than 20000Hz cannot be heard by human ears.

Different animals have a certain range of frequencies for hearing, and they vary greatly. Bats are capable of emitting and receiving ultrasound waves up to 120,000 Hz and rely on this ability to fly and hunt freely at night.

Sound occurs due to the vibration of an object, sound cannot travel in a vacuum, and there must be a medium for the propagation of sound

So the answer is: vibrationmedium

Answer B Analysis: Sound is produced by the vibration of the sound emitter, and the propagation of sound requires a medium, and solids, liquids and gases can transmit sound

Answer: The vibration of the object will make a sound, and the sound will travel through the air to our ears, so we can hear the sound of the object;

Therefore, choose B Comment: Knowing that the reason for the sound is the key to solving this question, Huna, is a basic question

People have two ears, and Wu Rufang can perceive sound, so under the effect of binaural effect, the sound perceived by cavity fiber has a three-dimensional sense of aeguse

So the answer is: both ears

When the object (amplitude) is large, the sound we hear is (high); When the object (the amplitude is small), the sound is (low). The high and low of the voice is called (pitch).

When an object is near, the sound we hear is (high-pitched); When the object is (far away), the sound is (muffled). The high and low of the voice is called (pitch).

Note: This is the Doppler effect.

Yes, you can tell where they are by their voices.

Stereo refers to sound with a three-dimensional sense. The sound produced by nature is stereo sound, but if we record, amplify, etc., and then replay these stereo sounds, all the sound is played out from one speaker, and this reproduction sound (compared to the original sound source) is not stereotype. At this point, the original sense of space, especially the spatial distribution of sound clusters, is lost because all kinds of sounds are coming from the same speaker.

This replay is claimed to be monophonic. If the entire system from recording to playback can restore the original sense of space to a certain extent (it is impossible to restore it completely), then this kind of reproduction sound with a certain degree of spatial distribution characteristics such as azimuth hierarchy is called stereo sound in sound technology.

Answer B: There are two processes through which people can hear sound: one is the process of producing sound from the vibration of objects; The second is the process of sound propagation through the medium to our lead chain tympanic membrane, and only the sound emitted by the object can be heard only if there is both a sound emitter and the air in which the sound is propagated by stupid dust in option b