MAGNETIC LEVITATION

This is completly in my language. Sorry for any launguage errors...

Levitation i process in which we hold a thing i the air witout any support. We know certain matals when cooled below critical temperature become superconductors.

For a while i was wondering how magnets are levitated in air using superconductors. Then I studied meissner effect.

For more information see : http://en.wikipedia.org/wiki/Meissner_effect

We know these superconductors are completely diamagnetic. It due to the week attraction force between free electrons due to which they forms pair and matal become completely diamagnetic(which also the reason for superconductivity). Diamagmetic properties are always present in the matter but are dominated by ferromagnetic and paramagnetic propertise. Only in superconductors we get complete diamagnetic property.
We know completly diamagnetic susbstances repels any kind of magnetic feild. Thats why the magnetic field line dosent enters the superconductor as shown in below
image...

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Now we know that a cooled super conductor will always be repelled by a magnet. So now we can levatiate a magnate as superconductor will repel it too. Above a super conductor as show below in a image and next in a video :
Image:

 
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Vedio:

Now under this system it is quite intresting to know that super conductor will attract and repell the magnet at the same time. Thats why the magnet will not just fly off and will levitate at fix point. And also if pull the magnet adove the super conducture will get pulled too. This attraction and repulsion at same time is due to Magnetic flux trapping which i dont have knowledge about.

More Information

This a the principle used by Maglev trains. But in place of superconductors they have to use electricity bacause such low temperatures cannot be maintained. Which causes a lot of eclectricity comsumption. Imagine if we could make a metal which would ba a superconductor at normal temperature we could then use the above principle of levitation to get free levitation and of coure save termendous amount of energy.
Actually a super conductor a develops some electric current at the surface to cancel out the magnetic field but this current is coserved due supedconductive propertise which also the reason for the stability of the levitation.

Validated by Anurag sir.

(Director Anurag Tyagi Classes)

By Sparsh Bhonwal XII C

Bhai Parmanand Vidya Mandir

Surya Niketan Delhi-92