# What are Sound Waves?

Sound waves are the pattern of disturbance caused by the energy traveling away from the source of the sound. Sound waves are longitudinal waves. This means that the propagation of vibration of particles is parallel to the direction of the energy wave propagation. When the atoms are set in vibration they move back and forth. This continuous back and forth motion results in a high-pressure and a low-pressure region in the medium. These high-pressure and low-pressure regions are termed compressions and rarefactions, respectively. These regions are transported to the surrounding medium resulting in the sound waves traveling from one medium to another.

### Characteristics of Sound Waves

Sound cannot travel through a vacuum. This is very much in contrast with the property of light. Another difference that is above the scope of the syllabus is the fact that sound waves are generally longitudinal waves and light waves are transverse waves. But they’re not very different either. Let’s take a look at the characteristics of sound when propagating through air.

### Nature Of Sound

The sound produced by a guitar is different from the sound produced by a drum. This is because the sound produced by different sources have different characteristics. Sound can be characterized by its frequency, wavelength, and amplitude.

### Frequency of sound waves

The number of rarefactions and compressions that occur per unit of time is known as the frequency of a sound wave. The formula of the frequency of a wave is given as:

 f=1T

Where,

• f is the frequency of a sound wave and
• T is the time period.

### Wavelength of sound

The distance between the successive compression and rarefaction is known as the wavelength of a sound wave. The wavelength of the sound formula is given as follows:

 λ=vF

Where,

• f is the frequency of the sound wave
• v is the velocity of the sound wave.