Superconductor Question ?!?!? (1 Viewer)

[Ace-Pilot]

Alrite im a bit dis-oriented with trying to fully understand superconductors.

Which one is correct ?

1.Will a metal reject mag fields just by being cooled down to its critical temp (superconductor) ?

2.Or in order to reject a mag field will a metal need to be cooled down to a superconductor AND have it connected to a power source in order to have current flowing thru it ao it will be able to create its own mag field and then reject an external mag field ?

3.Or will a STATIONARY magnet ontop of a superconducotr somehow induce current into the superconductor wich in turn creates its own mag field to reject the external one ?

Any one know what im talking about ? This is confusing me to the shits.

 

[spice girl]

(1) is correct

 

[Ace-Pilot]

Thanx spice girl,

but if u got Jacaranda and u flip over to page 257 and check out figure 13.25.a and 13.25.b where is that current coming from ?

And that current also appears to be the reason why the external mag fields are being rejected in the superconductor.

 

[kaseita]

The current is inside the superconducting material - its just the free electrons moving around

and they are the reason why the magnetic field is rejected

If you read the section on energy storage using superconductors, you'll see that they can store the current, without being connected to a circuit, and the current just runs around in there.

same thing in these ones, except the current is just much much smaller.

ever seen the experiment? of the magnet floating above the superconductor that is. the superconductor isn't connected to any circuitry

 

[Ace-Pilot]

Hey thanx kaseita,

Now that makes sense, didn't know that about super conductors.

Cool so they can store current, that explains it.