Hello friends, let me ask a simple question, what do you think technically, when.. You see an electric wire? It answer is very simple most of us replied that they think about a conductor, after that they think about its insulation or insulator.
So here in this article I will explain that “what are conductors & Insulators?” and also we will cover semi-conductors….
As all of you know that electrical Resistance is a basic property of any metal or non-metal and on the basis of resistivity we categorize conductors and insulators.
What is Resistance and what is Resistivity?
As per ohm`s law resistance of any element is define as the ratio of applied voltage and current (which is flowing through it).
But here is a twist, Resistance of any material is highly depends on its shape and size. So if we are using a thin wire its resistance will be higher as compare to a fat wire.
Here Resistivity comes in to the picture. Because it is a specific measurement of resistance so shape and size doesn’t effect on resistivity. As in shown formula area of conductor and length of conductor is used to calculate resistivity.
At we can say “Resistivity is the quantity which is used to specify specific resistance is called Resistivity. It`s symbol is ρ (Rho) and unit is Ohm-meter (Ω-m)”.
On the basis of Resistivity we can categorize material in to conductor and insulator.
As shown in given image there are three bands or category, Conductor, Semi-conductor and Insulator.
What is Conductor?
On the basis of resistivity conductors are material which has very less resistivity. Here Silver and Gold metals are the best example of conductors; its resistivity is around 10-8 ohm-meter. Usually conductor has very low resistivity. This low resistivity allows free electrons to pass through material. When a voltage applied to material, last orbit electron leaves its atom and move towards electrical drift. Now this amount of free electron is depend on resistivity of material. If resistivity is low, freer electron will be release and if resistivity is high, less free electron will be there.
Generally Metals are good conductor. In industry Copper and Aluminum are used as a conductor wire in electric cables.
The electrical energy which is lost in free electron collision and other process convert in to heat. That’s why conductor and other electrical component become hot after passing of electric current.
What is Insulators
An insulator has just opposite properties of conductor. Conductors are used to pass current whereas insulators are used to block current.
On the basis of resistivity insulator have very high resistivity. Insulators are made by Non-metals. At atomic level they have less numbers of free electrons and the bonding energy of electrons are also very high as compare to conductor material. These electrons are not able to move as they are stuck with parent atom. So in Insulator there is no current flow even electric voltage is applied.
Insulators have very high resistances, it is in mega ohms and there are no changes in any variation of temperature or other factor. Examples of good insulators are PVC plastic, Wood, Rubber etc.
Insulators are equally important as conductor. In Industry PVC insulator is used to cover conductor wires, Rubber mats are used to protect technician during high voltage work.
Hope that you have found some points related to conductors & insulators.