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THE LASER SHOW

   
 
  

   We see red or blue laser everywhere.  It is a highly useful modern day discovery.  What is actually Laser light?  Let us dig deep.

     A candle emits light in all frequencies (colours) in all directions( composite light).  It is like crowd of people moving randomly.  A sodium lamp emits only yellow colour light (Monochromatic light).  It is like walking of uniformed soldiers , but out of step with each other.



    A laser beam is a single colour (single frequency) light.  Most important, the waves are emitted in phase.(synchronized waves) and travel in unison.  Since the waves are in step with each other, they reinforce themselves and produce highly intense energetic beam of light.  It is like,column of soldiers marching in rhythm.  They all strike the ground with their feet in unison repeatedly.  So they may even bring down a bridge.

     Laser light is produced by laser diodes and easily available.  The laser beam travels in perfect straight line without diverging like other forms of light.  Hence, people sent a laser beam to the moon; it is reflected by the moon's surface; received in earth; using the time of travel, moon's distance was calculated accurately.

     The laser can burn.  So data is written on the DVD by burning it with laser. (a pit for 0 and bump  for 1 - binary data).

   Laser can act like a knife.  So precision surgeries are done with it.
    Laser pencil act like a bullet.  So it can be used as a weapon.

    We cannot even feel the ordinary light rays.  But this light beam is concentrated and converted into weapon in the form of laser.  This fact is difficult to digest.

     Laser in any form is dangerous to your eyes.  So take care.  Do not take the light lightly.

Note: 1. White laser is impossible.  Since laser must have a single colour.
2. Holograms that is found in ID cards, credit cards etc, is produced only because of laser.
3. Today we use laser fence to stop the intruders.

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