Superconducters: Difference between revisions

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A work in progress by the renowned author Ian Sebastian.
A work in progress by the renowned author Ian Sebastian.


Hey Ian, I actually started this page a while ago and figured that that would be enough to go ahead and claim it as mine. The work is also mine.- Thanks, Savannah Lee.  I'm trying to upload a photo of the file history for you to see but it isn't actually working.
Hey Ian, I actually started this page a while ago and figured that that would be enough to go ahead and claim it as mine. The work is also mine.- Thanks, Savannah Lee.   




[[File:Savannahownsthis.jpeg]]
[[File:Savannahownsthis.jpeg]]
'''Superconductors'''- superconductors are materials that can conduct electricity (or current) perfectly, meaning that no energy is lost to electric resistance. In order to understand why this is cool and see some examples, it's important to understand what electrical resistance is and why it creates problems. They also exhibit can get rid of all magnetic fields present on the inside of the material itself, called the Meisner effect. For some cool practical applications, stay tuned until the end.


== Introduction to Resistance==
== Introduction to Resistance==


The reason why super conductance is a cool topic to learn about is because of electrical resistance (link here).  Electrical resistance is basically what causes things to wear out and devices to need to be replaced. You can "feel" it or see properties of it if you've ever felt a circuit, or even a laptop that's extra hot after long periods of use. It can easily be thought of as the obstacles that prevent water from flowing in a pipe, with water being the electrons. The material that the pipe is made of could present issues, as well as the size and shape of the pipe. For the most part, water will flow more slowly through a pipe than it would without a pipe.  
Electric resistance is a property of all metals and conductors except superconductors. It's also the reason why your devices get hot after long periods of use, and the reason why they wear out. This is due to the resistance of the wire that the current is trying to pass through. Resistance measures, most broadly, how difficult it is for electrons to pass through the wire. It's kind of like friction from mechanics in the sense that it saps out energy from what would otherwise be a perfect system.
 
It's easy to think about electric resistance in the same way as you would water flowing through a pipe, and the obstacles it might meet. We know from earlier that a larger wire will produce a larger flow of current in the same way that a larger pipe would allow water to pass through more quickly than water through a smaller pipe.
 
However, it's not as easy to get rid of electrical resistance as it sounds. In a conductor and current situation, electrons flow between metal ions to their endpoint. How well they "hold on" to these electrons is a measure of their resistance. Depending on the material that this is made up off, the metal ions will hold onto the electrons differently and cause them to flow through at a different rate. Electrons get distracted on the way to the end of the wire and lose energy as a result. But, in a superconductor, this is eliminated and the electrons are able to march from start to finish without losing any energy.  


The problem of electrical resistance has a lot of potential to create really cool electrical devices for the future. It's somewhat analogous to friction from physics 1 in the sense that it slowly leaches energy from a system until it reaches zero. Just like how without friction, you could kick a ball around the world without it stopping or slowing down, without electric resistance, you could create a circuit that would have a current flowing forever. This has really cool practical applications and could create all sorts of new technology for the future- imagine devices that didn't need to be charged, or super low energy prices. More on this later.
== How Superconductors Work ==


== How a Superconducter Works ==
When you lower the temperature of a metal, its resistance will decrease. You could demonstrate this by taking a basic circuit and freezing it- because of ohm's law, the bulb would start to glow brighter since there is a lot more current flowing through until it heated up and the effect was nullified. (V=IR, lowering R will raise I which will raise brightness). For most materials, taking them to absolute zero (or really close) will cause the resistance to decrease to almost zero, or at least improve from where it was,  but not quite zero. However, some materials, superconductors, lose all resistance to current. The difference between "almost zero" and "actually zero" is enough to give rise to some cool properties of superconductors. What is happening on the molecular level is that the atoms are not vibrating quickly enough to try to seek out electrons any more, and attractions are minimized to the point where the electrons can flow through with no resistance.


When you lower the temperature of a metal, its resistance will decrease. You could demonstrate this by taking a basic circuit and freezing it- because of ohm's law, the bulb would start to glow brighter since there is a lot more current flowing through. (V=IR, lowering R will raise I which will raise brightness). For most materials, taking them to absolute zero (or really close) will cause the resistance to decrease to almost zero, but not quite. However, some materials, superconductors, lose all resistance to current. The difference between "almost zero" and "actually zero" is enough to give rise to some cool properties of superconductors.  
Seems easy, right? All we have to do is get something down to absolute zero and we're good!- not quite. You've probably read about how difficult getting something to absolute zero is. If not, click here.


Obviously, having to cool something down to absolute zero, or very close, creates a lot of problems from a research standpoint alone. Some superconducters can exist under their particular critical temperature.
There are several types of superconducters that are able to get around this

Revision as of 14:53, 30 November 2015

A work in progress by the renowned author Ian Sebastian.

Hey Ian, I actually started this page a while ago and figured that that would be enough to go ahead and claim it as mine. The work is also mine.- Thanks, Savannah Lee.



Superconductors- superconductors are materials that can conduct electricity (or current) perfectly, meaning that no energy is lost to electric resistance. In order to understand why this is cool and see some examples, it's important to understand what electrical resistance is and why it creates problems. They also exhibit can get rid of all magnetic fields present on the inside of the material itself, called the Meisner effect. For some cool practical applications, stay tuned until the end.

Introduction to Resistance

Electric resistance is a property of all metals and conductors except superconductors. It's also the reason why your devices get hot after long periods of use, and the reason why they wear out. This is due to the resistance of the wire that the current is trying to pass through. Resistance measures, most broadly, how difficult it is for electrons to pass through the wire. It's kind of like friction from mechanics in the sense that it saps out energy from what would otherwise be a perfect system.

It's easy to think about electric resistance in the same way as you would water flowing through a pipe, and the obstacles it might meet. We know from earlier that a larger wire will produce a larger flow of current in the same way that a larger pipe would allow water to pass through more quickly than water through a smaller pipe.

However, it's not as easy to get rid of electrical resistance as it sounds. In a conductor and current situation, electrons flow between metal ions to their endpoint. How well they "hold on" to these electrons is a measure of their resistance. Depending on the material that this is made up off, the metal ions will hold onto the electrons differently and cause them to flow through at a different rate. Electrons get distracted on the way to the end of the wire and lose energy as a result. But, in a superconductor, this is eliminated and the electrons are able to march from start to finish without losing any energy.

How Superconductors Work

When you lower the temperature of a metal, its resistance will decrease. You could demonstrate this by taking a basic circuit and freezing it- because of ohm's law, the bulb would start to glow brighter since there is a lot more current flowing through until it heated up and the effect was nullified. (V=IR, lowering R will raise I which will raise brightness). For most materials, taking them to absolute zero (or really close) will cause the resistance to decrease to almost zero, or at least improve from where it was, but not quite zero. However, some materials, superconductors, lose all resistance to current. The difference between "almost zero" and "actually zero" is enough to give rise to some cool properties of superconductors. What is happening on the molecular level is that the atoms are not vibrating quickly enough to try to seek out electrons any more, and attractions are minimized to the point where the electrons can flow through with no resistance.

Seems easy, right? All we have to do is get something down to absolute zero and we're good!- not quite. You've probably read about how difficult getting something to absolute zero is. If not, click here.

There are several types of superconducters that are able to get around this