The following Topics and Sub-Topics are covered in this chapter and are available on MSVgo:
We all hear different types of sounds like the chirping of a bird, the noise of vehicles, music, the sounds of working machines. Some of these sounds are pleasant, while some sounds are intolerable. Why do we hear these sounds? How does the sound travel? Up to which level we could listen to these sounds?
These are some questions that come to our mind when we think about “sound“?
When anything vibrates, it creates sound waves. The loudness of sound depends on the intensity of vibration of the object.. Vibration is the to-and-fro motion of an object. Various activities cause vibration, such as striking, stretching, rubbing, blowing, shaking, rotating, scratching, etc.
(Frequency, v = 1/T, is defined as the number of completed oscillations per unit time)
(Longitudinal waves: Here, the particle moves in the same direction of wave propagation.)
Factors that affect the nature of propagation of the sound:
In humans, the vibrations are produced by vocal cords. The vocal cord is attached with muscles, which changes the expansion in the cords, and sound is produced.
We Hear Sound Through Our Ears
The ear converts variations in pressure (in the air) having audible frequency range into electrical signals. These frequencies are transmitted to the brain via the auditory nerve.