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Superconductors
As everyone knows, superocnductors have no resistance below certain temperatures. But, I was thinking, surely this means you could use a superconducter 1mm or even less to transmitt power long distance? Consequently, you could use low (say 12v) mains, and it wouldn't need to be AC. Is this the way it will go if superconductors are created that have high operating temps? I recnetly read about 5% of power is lost through transmistion. Of course, currently the cost of cooling something to -100 or less means you'd need more money to cool it than would be saved through not losing power through wires.
And here's my second. My above paragraph seems to make pretty much sense to me, except surely there must be a limit to the current they can take? After all, only so many electrons could physically go around a circuit at the same time before either they start travelling at speed of light or faster (not possible) or they are packed together too closely (start repelling each other?)
And one totally irrelevant question. I understand the max speed of anything is speed of light IN vacuum, or just below if it has mass. But, the speed of light in other materials e.g glass, is less than in a vacuum. Does this mean you could accelarate particles to a speed faster than the speed of light in that material? And if so, would this create a "light boom", e.g a sonic boom but with light? And if so, would this light emitted by the "light boom" have a particular wavelength relative to the speed of the particle? This whole paragraph seems a bit abstract and I've never heard of it before, but I think it's at least worth asking about?
And here's my second. My above paragraph seems to make pretty much sense to me, except surely there must be a limit to the current they can take? After all, only so many electrons could physically go around a circuit at the same time before either they start travelling at speed of light or faster (not possible) or they are packed together too closely (start repelling each other?)
And one totally irrelevant question. I understand the max speed of anything is speed of light IN vacuum, or just below if it has mass. But, the speed of light in other materials e.g glass, is less than in a vacuum. Does this mean you could accelarate particles to a speed faster than the speed of light in that material? And if so, would this create a "light boom", e.g a sonic boom but with light? And if so, would this light emitted by the "light boom" have a particular wavelength relative to the speed of the particle? This whole paragraph seems a bit abstract and I've never heard of it before, but I think it's at least worth asking about?
2 main problems
a) materials lose their superconductivity if the current is too great.
b) cost of cooling and keeping cool. Catastrophic if material suddenly loses superconductivity
You can get electrons moving faster through a material than light would. You then indeed get Cerenkov radiation emitted. Thats what gives beta emtters a blue glow when they are stored underwater. Nicely worked out.
a) materials lose their superconductivity if the current is too great.
b) cost of cooling and keeping cool. Catastrophic if material suddenly loses superconductivity
You can get electrons moving faster through a material than light would. You then indeed get Cerenkov radiation emitted. Thats what gives beta emtters a blue glow when they are stored underwater. Nicely worked out.
teachercol
2 main problems
a) materials lose their superconductivity if the current is too great.
b) cost of cooling and keeping cool. Catastrophic if material suddenly loses superconductivity
You can get electrons moving faster through a material than light would. You then indeed get Cerenkov radiation emitted. Thats what gives beta emtters a blue glow when they are stored underwater. Nicely worked out.
a) materials lose their superconductivity if the current is too great.
b) cost of cooling and keeping cool. Catastrophic if material suddenly loses superconductivity
You can get electrons moving faster through a material than light would. You then indeed get Cerenkov radiation emitted. Thats what gives beta emtters a blue glow when they are stored underwater. Nicely worked out.
Ah, I wondered if a) was true. Are different superconductors able to take
different currents before losing superconductivity, and is there a term for the maximum current?
I'm not an expert in this area - but i know there is a maximum field that that superconductor can sustain. That implies I think a maximum current.
