Li-Fi(Light Fidelity) future wireless communication

In future it is suspected that every light bulb will be replaced by LED's the reason is LI-FI .Li-Fi  is acronym for light fidelity.The word fidelity means the ability of the receiver to reproduce all the signals.Light fidelity indicates transmission of data or information through light or illumination. The inventor defines it simply if LED is ON you transmit a digital '1' and if it is OFF you transmit a digital '0'.Li-Fi is the  next version to Wi-Fi(wireless fidelity) as it overcomes some of the limitations of Wi-Fi like speed,application areas like medical and in aircraft,outreach in remote areas etc.
NEED FOR LI-FI:
When you are using mobile phone or pc connected to wireless internet we have to compete for bandwidth and sometimes we get frustrated with slow speeds when more than one devices are connected. To solve this problem german scientist Herald Hass found an alternative way and he calls it with "data through illumination".He conveys that in future communication is done through Light in a room.
HOW IT GONNA WORK?
Li-Fi is transmission of data through illumination by taking fiber out of fiber optics by sending data through LED(light emitting diodes) light bulb that varies its intensity faster than human eye can follow.As said before  if LED is ON you transmit a digital '1' and if it is OFF you transmit a digital '0.As the reaction time of LED's to respond to the changes is very fast the transmission of data will also be fast. Theoretical calculations had proven that the rate of data transmission would be 224 giga bits per second.
*The requirements to adopt this technology are some LED's and controller that code data into those LED's
*Since it just uses light ,it can be used safely in aircraft and in hospitals that are prone to interference from radio waves.
*Simply radio waves are replaced by light waves in new method called Li-Fi.
*This method of using rapid waves of light to transmit information wirelessly is referred as Visible Light Communication(VLC) the transmitting frequency in VLC is around is 400Thz to 800Thz.
MAJOR APPLICATION AREAS OF LIFI:
1.IN FIELD OF MEDICAL:
Most hospitals donot allow Wi-Fi to enter into operating rooms due to radiation concerns and even it is lagged by some other cellphones or ipods, but communication is necessary in operation theaters  to treat patients.
LI-FI overcomes it.I think many of we know about the properties of light like inteference,diffraction ,polarization etc.Diffraction means bending up of light around the edges or obstacles.This property helps LI-FI to increase its efficiency.
2.AIRLINES: Where radio waves are not much efficient.
3.OUTREACH IN REMOTE AREAS:As the equipment for Wi-Fi is necessary, it is not possible to lay plant anywhere but since here in LI-FI it is through light we just need LED's and a controller.
4.UNDERSEAS:As it is difficult to lay optical fibers beneath water, it is better to communicate with help of light and as salt water is good conductor of electricity it is easy to work with LI-FI
5.FAST TRANSFER OF INFORMATION:As LED's ON and OFF very quickly which gives nice opportunities for fast transmitting the data.  

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chemistry concepts

                           Universe is composed of  matter,during vedic period in india ,maharshi kanada proposed that matter is composed of smallest particles such as "anu" and "paramanu". later a greek philospher proposed that matter consists of smallest particles called "Atoms" meaning indivisible , Atoms combine to form "compound atoms",which later on called as molecules. According to modern theories Atoms contain positive charged nucleus and negatively charged electrons. Nucleus further contain protons which are positively charged and neutrons which are neutral, combinely both protons and neutrons are called Nucleons. Mass of electron is negligable while mass of proton is 1837 times of electrons. J.J Thomson is the person who discovered the cathode rays(electrons which are travelling from cathode to anode and these are invisible.G.J Stoney named these cathode rays as "electrons".

  Two types of forces are present in atom a)force of attraction between the electrons and protons(Attractive force).This force pulls the electrons towards the nuclues. second type of force is b)the revolving electrons experience a centrifugal force directed away from the moving path of electrons.This force pulls away the electrons from nucleus ,since these two forces are equal and opposite ATOM is stable.

IF THESE ATOMS ARE STABLE WHY THEY COMBINE?

It is known that inert gases like Ne(10),Ar(18),Kr(36) have stable electronic configuration and have no tendency to combine with other atoms.Elements like fluorine(9),chlorine(17) are very reactive as they are short of one or two.Similarly atoms of Alkali metals like Li(3),Na(11),K(19) are very reactive and form numerous compounds.

WHY SOME ARE REACTIVE AND SOME OTHER NOT?

In the above paragraph i used the word "electronic configuration",it is defined as systematic arrangement of electrons in the atomic orbits.The maximum number of electrons present in each orbit is generally given by 2nsquare.(n=number of orbit) i.e 1st orbit -2,2nd orbit-8,3rd orbit-18...

*Electrons present in the outer most orbit of an atom are known as valence electrons and based on these atoms are said to be reactive or not.Now observe electronic configuration of inert gases they have 8 electrons in their outermost orbit except helium(2) all are stable in inert gases.

*Halogens have 7 electrons in outermost orbit.Normally every atom has tendency to attain nearest noble gas configuration and become stable,As they are 1 electron short they combine with another atom to have 8 electrons which provides them with much stability.

This is perfect reason for "chemical bonding".Atoms combine to form molecules so "molecules are much stable than atoms".

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