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SOUND AND LIGHT SHOW

     When a body vibrates- for example voice box in the throat- sound waves are produced.  They travel as a pressure wave in the air medium. In atoms, when an electron accelerates, it looses energy in the form of light waves.  They travel as electromagnetic wave without the help of the medium.  

     Since sound is produced by big objects, their wavelength is also big. (From 17 meter to 17 mm).  Since light is atomic phenomenon, their wavelength is smaller.  (From 400 nanometer to 700 nanometer).

     We know , the speed of sound and light is vastly different(330 m/s and 3*10^8 m/s).  Hence we see the lightning first and hear thunder later.

     Frequency of sound waves is responsible for the pitch and tone.  Frequency of light waves is responsible for the colour and energy.

     Sound can be electronically amplified.  The amplification of light is LASER.

     TWO eyes are responsible for the depth of a scene.  That is, you can roughly calculate the distance between you and the house you see.  TWO ears are responsible for the depth of sound.  That is, you can roughly estimate the direction and distance of  sound.

     Sun is the major source of light.  It contains seven natural colours.  The music contains seven basic sound notes.  Colours can be composed into beautiful art.  Music notes can be composed into beautiful symphony.

     Sound waves bend around the doors and windows.  Light waves also bend around the objects.  But we require small slits comparable to its wavelength to observe the bending of light(diffraction).

     Sound is echoed by mountains, caves and light is reflected by mirrors.

    High frequency light and sound waves cannot be seen and heard by humans.  But some animals can.(ultraviolet, ultrasonic).

     light waves in opposite phase can cancel each other and produce darkness.  Similarly sound waves in opposite phase can cancel each other and produce silence.  This interference experiment can be done in a laboratory.

Psychologically, ink darkness is frightening and dead silence is deafening.

Science update: US scientist have tracked a shark covering a sea distance of 8000 km in just 142 days.     

Comments

  1. The readers( even those who does not have science background) will understand and will come to know about characteristics, differences and the properties of sound and light after reading this.
    Very nice post Sir.

    ReplyDelete

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