is there a superconducting limit?

[Jjoshua2]

so v=i/r normally. with no resistance there is infinite current with any voltage. What my actual question is, "Is there a limit on how much current a superconductor can take before it won't take any more or it quite superconducting, and which one comes first?"

I'm thinking about a superconducting backbone grid for the US that would be kind of like the internet backbone, to allow the peak time shift to use juice from other timezones. I was wondering if you would need a mega piece of superconductor to run a several states power through or if even a small wire that was cold enough would work.

 

[chorb]

v = i * r

 

[Matthiasa]

There is a limit but it depends on the material being used among other things.

 

[Freshgeardude]

if I remember correctly, conductors are just a bunch of electrons bunched up, so a point will come when it wont be able to hold any more electrons

 

[manowar821]

Originally posted by: freshgeardude
if I remember correctly, conductors are just a bunch of electrons bunched up, so a point will come when it wont be able to hold any more electrons

Electrons are fucking SMALL though.

 

[Minerva]

this should be posted in the highly technical forum!

 

[Mark R]

Superconductors have a 'critical current' - if you go over that level, the wire goes back to normal conductivity. The critical current depends on the material, temperature and the size of the wire (circumference, not cross sectional area - as electrical current cannot penetrate into a superconductor, it only flows on the outer surface).

The lower the temperature, the better the current handling. E.g. the LHC superconducting magnets operate at 1.9 K, whereas normal helium cooled superconducting magnets (e.g. MRI scanners) operate at 4 K. The reason is to get higher currents to flow in the magnets, so that they can make them stronger.

 

[ConstipatedVigilante]

You can superconduct my current.

 

[PlasmaBomb]

Info on superconduction.