Skip to main content

SAY HELLO THROUGH WIRE OR AIR OR......

   

     Men communicated through sign language long back.  It is still used by physically challenged people.  Men invented language.  It paved way for the oral and written communication.
     When distance increases, how to communicate?  Written message on palm leaf, cloth,paper  were sent on horses, trains and ships.  Today, we call it snail mail.  But it is still vogue.
     Telephone , telex, telegram were invented.  Messages were sent through wires with electricity. Voice was converted into electrical signal and sent through telephone cables.  In telegram, two sounds represented each alphabet in English.  The letters are converted into sounds and sounds into electrical pulses.  Then the pulses travel from one post office to another.  The postmaster had to undergo special course to decipher the message in those days.
     Radio was born.  That is, Radio waves receiver set.  Speech and songs were converted into electricity than into Radio waves(electromagnetic waves) and transmitted.  Received by radio set and converted back into songs.  It is one way wireless communication.  distance was no longer a matter.  Walkie-talkie came for two way short distance wireless communication.
    TV appeared.  Picture transmission-same principle as radio.
     The internet(international network)  revolutionized the way we communicate.  All computers in the world were initially connected through telephone lines.  Now they are connected through dedicated cables, wires,or even without wires.  The internet is ON 24X7.  No holiday.  You can pay bills on the Sundays.  Millions of emails (electronic mails) travels around the globe in seconds.
    The big revolution; the smart phone.  Any one can contact any one anywhere on the globe instantly at zero cost.  Video phone become reality.  The smart phone is also hooked on the internet.
  Today, you can down load any book, any song, any movie, any daily magazine, any speech, any video, information on your smart phone, tablet and PC. With the smart phone, the world is in your pocket.
    The communication is so improved that an expert surgeon can do surgery remotely.  Tele-medicine is a reality.  IOT-Internet of things is coming. you will be able to control your home fan, fridge, AC, doors ... from anywhere in the world.
     In those days, in the case of emergency, they sent the SOS (save our souls) message using drums, fire, smoke.  Even today, we send SOS using torchlight, whistle etc. (Listen to airplane safety precautions)

Principle of communication:
     Info (text, audio, video,...) to electrical signals to electromagnetic waves (radio waves) or light.  Sent through glass fibers (optical cable) or through air.  Received and the process  is reversed.

     In the near future, the speed of internet will increase so that we can down load a movie in seconds and watch it for hours.
     Is the communication revolution a ban or a boon?  It is open to debate.  You can either save a person with knife or kill him with it. 

Foot note:
     "It takes a fraction of a second to send a message to the other side of the globe but it takes years to send a message from outside the head to inside the head". 
---------------------------------------------------------------------------------------------- 

Comments

Post a Comment

Popular posts from this blog

THE EARTH, A SUPER ORGANISM

     JOIN MY COURSE: "Become a programmer in a day with python"       A man called 'love lock' (what a name) proposed a theory called Gaia theory, named after Greek Goddess.      It says, "Earth is a self-regulating organism like a human being.  The organic life in it interacts with in-organic matter and maintains atmosphere, temperature and environment".  Hence the earth is still suitable for the life to thrive.      Imagine, in a particular place, there are lot of flowers.  Some flowers are white and some are darkly coloured.  We know, white reflects light and heat while dark absorbs the same.  White flowers can thrive in hot climate.  But dark flowers requires cold climate.  The absorption and reflection balances and the environment reaches average, warm temperature at which both the flowers can co-exist.  This is the essence of "Gaia" theory.      On our earth, the oxygen constitute 20% of the atmosphere.  The oxygen level is always mai
3 comments
Read more

THE PARABOLA

          A jet of water shooting from a hose pipe will follow a parabolic path.  What is the so special about parabola.    Y= x^2 Draw a graph for the above equation.  It will result in a parabola.  This parabola is also called unit parabola.  Any equation involving square will yield a parabola. Example:  Y = 2x^2 +3x+3 (also called quadratic equation)    X= 2 and -2, both  satisfies the equation 4 = X^2.  Parabolic equations always have two solutions.     Any motion taking place freely under gravity follows parabolic path. Examples:   An object dropped from a moving train,   A bomb dropped from flying plane,  A ball kicked upwards.      If a beam of light rays fall on the parabolic shaped mirror, they will be reflected and brought to focus on a point.  This fact is made use of in Dish Antenna, Telescope mirrors, etc.      Inverted parabola shape is used in the construction of buildings and bridges.  Because the shape is able to bear more weight.      A plane
Post a Comment
Read more

DISORDER IS THE "ORDER OF THE DAY"

         Imagine a balloon full of air.  The air molecules are moving randomly inside the balloon.  Let us pierce the balloon with a pin.  The air rushes out.  Why should not the air molecules stay inside the balloon safely and ignore the little hole?  That is not the way the world works.  The molecules always "want to occupy as many states as possible".  Hence the air goes out in the open to occupy more volume.   The things always goes into disorder (entropy) and the disorder increases with time.  The above statement is what we call "second law of thermodynamics".      Consider a cup of coffee on the table. Suppose the heat from entire room flows to your cup of coffee, the coffee will boil and the rest of the room will freeze.  Freezing means bringing things to order and arrangement.  It violates the second law.  Hence it will never happen.  Hence heat must flow from high temperature to low temperature and not the other way.        The air molecules in y
Post a Comment
Read more