Sound

 WHAT IS SOUND?

Sound is a thing which plays an important role in our lives. How do you understand that someone is calling you ? by the help of sound. In our daily lives we hear different varieties of sounds in our surroundings whether it is the sound of your school bell or the sound of televisions at your houses. It helps us to communicate with other ones. In your mind some queries come out,they are the following:

How is sound produced?How does it travels distance from one place to another place? How do we hear sound? And with the help of which parts of our body?Why are some sounds have variations (louder or thinner tha others)? We will discuss it about.

HOW SOUND IS PRODUCED ?

Sound is produced by vibrating bodies as I have earlier given an example of your school bell.Feel the vibration when a metal plate is producing sound, did you feel anything? it is vibrating. As we known that the plate is vibrating ,But what is vibration? Vibration is the to (when the plate is hit) and fro (the motion or vibration comes back) and forth motion of an object is called Vibrations .          

Some of the vibrating bodies produces sound in some of the cases the vibrations are easily visible to us, for example : When a container is filled with water and stroke, we can see the vibrations in the water. But in most cases, their amplitude is so small that we cannot see them. However we can feel them by their vibrations. And amplitude is the standard unit (SI) of measuring vibrations. 

HOW SOUND IS PRODUCED IN HUMANS ?

In humans the sound is produced by the voice box . The voice box is also called the larynx. It is present in the throat, and at the upper end of the windpipe.When we swallow a hard bump that seems to move this part of our body is known as the voice box or larynx. Two vocal cords are stretched across the voice box in such a way that it leaves a narrow slit between them for the passage of air. When the lungs force air through the slit ,the vocal cords vibrates for producing sound. Muscles attached to the vocal cords can make the cords tight or loose when the vocal cords are tight and thin the type of quality of voice is different from that when there are loose and thick.

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DO YOU KNOW?

Vocal cords in male are 20 mm long and in women these are of 15 mm (5 mm shorter.) Children have very short vocal cords this is the reason why the voices of men women and children are different.

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