A sound wave is a periodic disturbance which travels through a medium transferring energy from one point to another without causing any permanent displacement of the medium. Sound needs a medium to travel. This note explains us about sound, echo, reverberations and absorption of sound along with its measuring components.
Echo is the reflection of sound by a hill or a large building some distance away. When sound falls on a surface, it is partly reflected and partly absorbed. If there are a number of reflecting surfaces near one another, a series of reflection takes place. Such sound is called reverberation. This note provides information about echo, application of echo, absorption of sound, reverberations and some numerals.