Physics Course/Types of Waves/Sound Waves

Sound Wave
Sound wave is a Longitudinal Wave. When Sound Wave travels through air it will create expanding or shrinking column of airs called Rarefraction and RareExpansion.
 * Sound Wave | ||  |  ||

Sound Wave Characteristics

 * 1) Sound does not exist in vacuum.
 * 2) Sound wave requires medium of matter to spread itself . Sound wave travels through any medium Solid, Liquid , Gas
 * 3) The speed of Sound wave varies with Pressure and Temperature of the medium . Sound wave travels at a speed v = λ f . At Standard Pressure & Temperature in air the speed is calculated equal to v = 333 m/s
 * 4) Sound Wave that is audible to human ear is in the frequency range 20Hz - 20KHz.

Sound's Effects
When Sound wave travel through a medium if there is a blocking object that has a height greater than the wavelength of sound wave. Sound wave will suffer from the following effects

Reflection

 * Sound wave being reflected back to the medium it comes from and can create interference with other wave in the medium
 * Ray_Diagram_2.PNG

Refraction

 * Only part of Sound wave is passing through . Sound does not reach its destination
 * Ray_Diagram.PNG

Diffraction

 * Wave travels through narrow opens
 * Two-Slit_Diffraction.png

Interference

 * When two sound waves travel toward each other will interfere either Constructively or Destructively to produce different sound interferences like Noise, Echoe, Intermittent, /No sound/

Tele Communication
In Tele Communication, in order to carry Sound wave over a long distance sound wave must be mixed with a high frequency carrier wave in a process called Modulation.

In Radio Communication, There are 3 modulations methods are used in mixing Sound wave and Carrier wave namely AM - Amplitude Modulation, FM - Frequency Modulation, PM - Phase Modulation.

In analog electronics, AM and FM is widely used. In digital electronic, PM is used

Reference

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