Wireless Electricity

WiTricity is nothing but a name given to wireless electricity. Transmission of electrical energy  from one object  to another without  the use of wires  is called as WiTricity. WiTricity will ensure that the cellphones, laptops, iPods and all other power hungry devices get charged on their own, eliminating the need of plugging them in. Even better, because of WiTricity some of the devices won't require batteries to operate.

Well lets see a brief introduction to its inventor and then to the working part:

Invented by Nikola Tesla(1856 - 1943).

The idea of wireless electricity has been around since the early days of the Tesla coil.Tesla invented the alternating-current generator that provides your light and electricity, the transformer through which it is sent, and even the high voltage coil of your picture tube. The Tesla Coil, in fact, is used in radios, television sets, and a wide range of other electronic equipment - invented in 1891, no-one's ever come up with anything better.

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Then the initiate was taken by the group of MIT scientists, "WiTricity" (as these scientists call it).They demonstrated the ability to power a 60-watt light bulb from a power source seven feet away without wires might not seem like the most impressive of feats, but the technology behind it has massive implications for how we live our tech-filled, power-hungry lives.The  first  copper  coil  (24  inches  in  diameter) was  connected  to  the
power source and  the second was connected  to  the bulb, and were
made  to  resonate at a  frequency of 10 MHz. The bulb glowed even
when  different  objects  (like  a wooden  panel) were  placed  between
the two coils. The system worked with 40% efficiency and the power
that  wasn't  utilized  remained  in  the  vicinity  of  the  transmitter  itself,
and  did  not  radiate  to  the  surrounding  environment.

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WORKING:

The basic principle behind the "witricity" is "RESONANCE COUPLING".The  electric  power  from  the  power  source  causes  the  copper  coil
connected  to  it  to  start  oscillating  at  a  particular  (MHz)  frequency.
Subsequently, the space around the copper coil gets filled with nonmagnetic
radiations.  This  generated magnetic  field  further  transfers
the power  to  the other copper  coil  connected  to  the  receiver. Since
this coil is also of the same frequency, it starts oscillating at the same
frequency as the first coil.Which is the "coupled resonance".

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