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SOUND OF MUSIC

      


                     ADVT:  REFURBISHED MOBILES IN AMAZON

     When a bell is struck, it vibrates with a certain frequency (Number of vibrations per second).  The vibrating bell pushes the air molecules around it.  Hence air pressure variations are created with the same frequency.  These pressure variations travel as a sound wave and reach our ears.  The ears sense it. The brain interprets as a certain sound.

    Frequency is the main feature of sound and music. It is measured in Hertz-Hz. One Hertz is one vibration or one cycle per second.

    How the stringed musical instruments like the violin, the guitar produces music-sound of various frequencies?  Let us find out.

       Frequency of vibrating string = 1/2*length*(root of (tension/linear density)

      According to the formula, one can change the frequency in three ways. 1. tightening the string -tension changes 2. Using a thicker string -linear density 3. using fingers on frets - length changes.

    Mainly frequency is changed by changing the length of the string. Frequency is inversely proportional to the length of the string. If we halve the length of the string, the frequency will double.

    The frequency is easily changed by using fingers as shown in the figures.

     

       As the length of the vibrating string decreases, the frequency increases. 

        

               The seven basic musical notes and their frequencies are given below.

    do           SA               240

    re           Re                270

   mi           GA               300

   fa            ma               320

   soi           pa                360

    la           dha               400

   si             Ni                480 

Latin        Indian      Frequency Hz

                  By moving fingers on the strings, we can create sounds of various frequencies or musical notes. By combining musical notes rapidly, we can produce a composition- a melody, a symphony, a song. 

        Rainbow is an eye-candy. Basically, they are light waves. But each color has its own frequency. Similarly, a song is ear -candy. Basically, it is sound waves. But it is composed of various frequencies.  

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NOTE 1; We understand that low-frequency means long string. That is why low-frequency instruments like cello, the bass is larger than the violin.

NOTE 2:  women's voices have a higher frequency than men's.

NOTE 3: Higher frequencies which are multiples of the fundamental frequency are called harmonics or octaves.

NOTE 4: When we say "sa' the voice box in the throat vibrates at 240hz. When we say "Re' it vibrates at 270 Hz and so on.


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