Wireless Power.

Recently there was a competition about technical reviews,i was wondering what to do,then suddenly was glancing through one of  IEEE magazines there i saw Wireless Power Transmission,i was at first dazzled  then i researched about wireless power transmission.It is one of the revolutionizing technologies of this century.The principle behind this wonder is electromagnetic resonance.Though it seems complex at beginning ,it was easy to get a picture of this technology.I would explain using  an example,consider a normal transformer the principle behind it's working is electromagnetic induction,the magnetic flux linkage takes place ,the core helps in magnetic flux linkage without it would be impossible to link flux.Now,let us modify a little by now taking out the core and replacing it by air,so now there will only primary coil and secondary coil.The problem in this will be that the flux linkage will be almost negligible.To overthrow this ,we use the principle of resonance to link  both,simply adding a capacitor in parallel with inductor will create L-C oscillator circuit,then the primary and secondary will be critically tuned to same frequency,thereby linking maximum possible flux.

  At MIT in 2007,an experiment was conducted using a 60watt bulb at a distance of 2m and resonant frequency used was 9.9MHZ,there was an efficiency of 40%.