As long as the object vibrates, sound is produced

It should be said that all of them are true, but they understand it in different ways.

There are two basic conditions for sound to reach the human ear and be perceived. First, there is a sound source; Second, there is a medium of transmission.

Objects can make sounds when they vibrate, so your teacher is right.

However, for the sound emitted by a vibrating object to be perceived, there must be a medium of propagation to transmit the sound. If you see an object making a sound in a vacuum, you can't hear the sound because there is no medium to transmit the sound to your ears, and the so-called vibrating object doesn't necessarily make a sound.

So when you take the exam, it depends on who makes the question.

As long as the object vibrates, it does not necessarily produce sound.

Mechanical vibrations, which must propagate in a medium in order to produce mechanical waves. Sound waves are mechanical waves, and only a medium that vibrates and transmits vibrations can produce sound.

This statement is not true!

Sound is produced by the vibration of an object, but a medium of propagation is required, and without a medium, no sound is produced. In a vacuum, for example, the vibration of an object does not produce sound.

Wrong. If it is in a vacuum, it will not; In addition, if the amplitude of the sound emitter vibration is not enough, it is not possible

When an object vibrates, something is wrong.

There are two aspects that determine sound: one is that there is an object vibrating, and the other is that there is a conductive medium.

As long as there is sound, there will be objects that vibrate.

Sound is produced by the vibration of an object.

Not necessarily. There are two conditions for the production of sound, one is that there must be a sound source, that is, a vibrating object; The second is to have a medium for transmitting sound, such as air. An object that vibrates in a vacuum does not make any sound.

In the air, as long as it vibrates, the air next to it must also vibrate. But you may not hear it. One is that the amplitude may be too small, that is, the sound is too small. The second is that the frequency may not be in the range that the human ear can hear, and this range is roughly 20Hz 20000Hz

If it's an exam, this sentence is definitely wrong. The main reason is that there must be a medium for sound to be produced, and this sentence does not indicate that it is vibrating in a medium.

All kinds of sounds in the air, whatever form they take, are caused by the vibrations of objects: when the drum is beaten, the sound of the drum is heard, and the vibration of the drum surface can be felt; A person is able to speak because of the vibration of the vocal cords of the throat; The sound of a steam whistle and the roar of a jet plane is caused by the vibration of the gas during exhaust. In conclusion, the vibration of an object is the source of the sound, and the object that emits the sound is called the sound source.

The sound emitted by the sound source must pass through an intermediate medium, and the most familiar medium is air, which can transmit sound in addition to gases, liquids and solids. The speed at which vibrations propagate through a medium is called the speed of sound, and the speed of sound in any medium depends on the elasticity and density of the medium, so the speed at which sound travels varies from one medium to another: in liquids and solids it is generally much faster than in air, e.g. 1450 ms in water and 5000 ms in copper.

The speed at which sound travels through the air also increases with the temperature of the air.

This statement is correct.

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Sound is a sound wave produced by the vibration of an object's hand. It is a wave phenomenon that propagates through a medium (air or solid, liquid) and can be perceived by the auditory organs of humans or animals. An object that initially emits vibrations (vibrations) is called a sound source.

Sound travels in the form of waves that vibrate (vibrate). Sound is the motion formed by the propagation of sound waves through any medium.

Sound is a wave. Sounds that can be recognized by the human ear (frequencies between 20 Hz and 20000 Hz) are called sounds.

In physics, sound is generated by the vibration of an object, and the object that is emitting sound is called the sound source. The number of times an object vibrates in one second is called the Bu brother frequency, and the unit is hertz, the letter Hz. The human ear can hear the sound of 20 20000 Hz, and the most sensitive is the sound between 200 and 800 Hz.

The propagation speed of sound in different media is generally solid, liquid and gas (exceptions, such as: cork 500m s, less than kerosene (25), distilled water (25), etc.), and the propagation speed of sound is related to the type of medium and the temperature of the medium.