Electrical conductivity: Difference between revisions

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[[Category:Done 2018-04-30]]
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[[File:power line.jpg|300px|thumb|Figure 1. High voltage power lines are made out of aluminum, because of it's high electrical conductivity.<ref>Wikimedia Commons [Online], Available: http://commons.wikimedia.org/wiki/File:Ligne_haute-tension.jpg</ref>]]
<onlyinclude>'''Electrical conductivity''' is a property of materials that determines how well a given material will conduct [[electricity]].</onlyinclude> Electrical conductivity is closely related to [[resistivity]] (which is more commonly used):
<onlyinclude>'''Electrical conductivity''' is a property of materials that determines how well a given material will conduct [[electricity]].</onlyinclude> Electrical conductivity is closely related to [[resistivity]] (which is more commonly used):


<m>\sigma = \frac{1}{\rho}</m>
<center><math>\sigma = \frac{1}{\rho}</math></center>


where <m>{\sigma}</m> is the conductivity (in [[meter|m]]/[[Ohm]]) and <m>\rho</m> is the resistivity (in [[Ohm]]/[[meter|m]]). To determine the resistance of a [[wire]] (which could be made of almost anything: [[copper]], [[aluminum]]; this equation even works for wood!), use:
where <math>{\sigma}</math> is the conductivity (in [[meter|m]]/[[Ohm]]) and <math>\rho</math> is the resistivity (in [[Ohm]]/[[meter|m]]). To determine the resistance of a [[wire]] (which could be made of almost anything: [[copper]], [[aluminum]]; this equation even works for wood!), use:


<m>R = \rho \frac{A}{l}= \frac{A}{\sigma l}</m>
<center><math>R = \rho \frac{A}{l}= \frac{A}{\sigma l}</math></center>


where <m>A</m> is the cross-sectional area of the wire (in m<sup>2</sup>) and <m>l</m> is its length (in m).
where <math>A</math> is the cross-sectional area of the wire (in m<sup>2</sup>) and <math>l</math> is its length (in m).


Electrical conductivity is closely related to [[electrical conductance]]. Electrical conductivity is a property of the material itself (like [[silver]]), while electrical conductance is a property of a particular electrical component (like a particular [[wire]]).
Electrical conductivity is closely related to [[electrical conductance]]. Electrical conductivity is a property of the material itself (like [[silver]]), while electrical conductance is a property of a particular electrical component (like a particular [[wire]]).
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Electrical conductivity can be defined as how much [[voltage]] is required to get an amount of electric [[current]] to flow. This is largely determined by the number of [[electron]]s in the outermost shell; these electrons determine the ease with which mobile electrons are generated. Another factor--but a less important one--is the number of atoms per unit [[volume]], which determines the number of electrons that will readily move in response to an [[electric field]]. Materials with high conductivity, like copper and aluminum, are called [[conductor]]s. Materials with low conductivity, like rubber and glass, are called [[electrical insulator]]s (or just insulators when there's no possibility of confusion with thermal [[insulation]]). Another special class of materials like [[silicon]] and [[germanium]] are in between and are called [[semiconductor]]s.  
Electrical conductivity can be defined as how much [[voltage]] is required to get an amount of electric [[current]] to flow. This is largely determined by the number of [[electron]]s in the outermost shell; these electrons determine the ease with which mobile electrons are generated. Another factor--but a less important one--is the number of atoms per unit [[volume]], which determines the number of electrons that will readily move in response to an [[electric field]]. Materials with high conductivity, like copper and aluminum, are called [[conductor]]s. Materials with low conductivity, like rubber and glass, are called [[electrical insulator]]s (or just insulators when there's no possibility of confusion with thermal [[insulation]]). Another special class of materials like [[silicon]] and [[germanium]] are in between and are called [[semiconductor]]s.  


Generally, most [http://hyperphysics.phy-astr.gsu.edu/hbase/pertab/metal.html#c1 metals] have high conductivity (which is another way of saying metals tend to be [[conductor]]s), because the electrons in their outermost shell can move easily. Non-metals tend to have low conductivity.
Generally, most [[metal]]s have high conductivity (which is another way of saying metals tend to be [[conductor]]s), because the electrons in their outermost shell can move easily. Non-metals tend to have low conductivity.<ref> Hyperphysics, conductors and insulators, Accessed May 9th, 2018: http://hyperphysics.phy-astr.gsu.edu/hbase/electric/conins.html#c1</ref>


To learn about the physics behind conductivity please see [http://hyperphysics.phy-astr.gsu.edu/hbase/electric/conins.html#c1 hyperphysics].
To learn about the physics behind conductivity please see [http://hyperphysics.phy-astr.gsu.edu/hbase/electric/conins.html#c1 hyperphysics].
== For Further Reading ==
For further information please see the related pages below:
*[[Direct current]]
*[[Alternating current]]
*[[Electrical grid]]
*[[Resistance]]
* Or explore a [[Special:Random| random page!]]
==References==
{{Reflist}}
[[Category:Uploaded]]
[[Category:Uploaded]]

Revision as of 17:18, 9 May 2018

Figure 1. High voltage power lines are made out of aluminum, because of it's high electrical conductivity.[1]

Electrical conductivity is a property of materials that determines how well a given material will conduct electricity. Electrical conductivity is closely related to resistivity (which is more commonly used):

[math]\sigma = \frac{1}{\rho}[/math]

where [math]{\sigma}[/math] is the conductivity (in m/Ohm) and [math]\rho[/math] is the resistivity (in Ohm/m). To determine the resistance of a wire (which could be made of almost anything: copper, aluminum; this equation even works for wood!), use:

[math]R = \rho \frac{A}{l}= \frac{A}{\sigma l}[/math]

where [math]A[/math] is the cross-sectional area of the wire (in m2) and [math]l[/math] is its length (in m).

Electrical conductivity is closely related to electrical conductance. Electrical conductivity is a property of the material itself (like silver), while electrical conductance is a property of a particular electrical component (like a particular wire).

Electrical conductivity can be defined as how much voltage is required to get an amount of electric current to flow. This is largely determined by the number of electrons in the outermost shell; these electrons determine the ease with which mobile electrons are generated. Another factor--but a less important one--is the number of atoms per unit volume, which determines the number of electrons that will readily move in response to an electric field. Materials with high conductivity, like copper and aluminum, are called conductors. Materials with low conductivity, like rubber and glass, are called electrical insulators (or just insulators when there's no possibility of confusion with thermal insulation). Another special class of materials like silicon and germanium are in between and are called semiconductors.

Generally, most metals have high conductivity (which is another way of saying metals tend to be conductors), because the electrons in their outermost shell can move easily. Non-metals tend to have low conductivity.[2]

To learn about the physics behind conductivity please see hyperphysics.

For Further Reading

For further information please see the related pages below:

References

  1. Wikimedia Commons [Online], Available: http://commons.wikimedia.org/wiki/File:Ligne_haute-tension.jpg
  2. Hyperphysics, conductors and insulators, Accessed May 9th, 2018: http://hyperphysics.phy-astr.gsu.edu/hbase/electric/conins.html#c1