Electrical insulators are materials through which electric charge does not flow freely. Insulators have high electrical resistivity.

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How is the relationship of resistance with the following items justified? [closed]

Can anyone practically explain me how 1. Resistance of a conductor increases linearly with increasing temperature? 2. Resistance of a semiconductor decreases with increase in temperature? 3. ...
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How to prove R value for insulation?

I ran some tests on different types of insulation. I heated water, and placed it into an insulated box. The temperature was recorded every minute, for the water, as well as the air. The insulation ...
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Work functions of ceramics/insulators

Is anyone aware of or know of a good source or means of estimating the work function of a ceramic material? Typically, work functions are given for pure elemental metals, rather than for compounds, ...
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Can the Fermi energy lie into the band gap?

Fermi energy $\rightarrow$ highest energy level filled at $T=0K$ Fermi level $\rightarrow$ Energy level where we have a chance of $50\%$ to find an electron. Now in my course text they say that for ...
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When a charged insulator is touched by a conductor, What really happens?

1-how does the conductor get charged although the electrons in the insulator are not free to move? 2-If the conductor material is connected to the earth, Will the insulator be discharged?
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Static electricity and insulators

I've read that Stephen Gray in his experiments on electricity, he has found that static electricity can be conducted -transferred- through an insulator thread made of silk. So, how could that happen ...
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What's the difference between insulators and topological insulators?

What's the difference between insulators and topological insulators? When I asked some people about this, they told me that "because the topological insulators have gapless edge states,...", but what ...
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Finding potential of conducting sphere coated by a dielectric shell

An uncharged conducting sphere of radius $a$ is coated with a thick insulating shell (dielectric constant $\epsilon_r$ out to radius $b$. This object is now placed in an otherwise uniform electric ...
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Preventing Electricity Leakage With Insulators

If we charge an object made of insulating material, the charges on it would leak to the medium as the time passes, due to the potential difference. I would like to know if there is a way to prevent ...
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I touched a tree that was touching an electric fence and got an electric shock. How is this possible if wood is an insulator?

I touched a tree that was touching an electric fence and got an electric shock. How was this possible if wood is an insulator? The tree wasn't wet either, and it was a pretty strong shock too.
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materials that repel positrons?

In this article is discussed at some length positron formation in metallic surfaces. Positrons have work functions that describe how much energy they have to receive in order to be extracted from the ...
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How to make charges of a charged conductor evenly distributed over the surface of the object?

Is there a way to make the charges of a charged conductor evenly distributed over the surface? I know the charges of a charged insulator are evenly distributed but I want to know that if there is a ...
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What is the best insulator for static charges? [closed]

I am trying to find a solid material that almost fully (since there is not a thing that can fully insulate electricity) blocks static charges from one layer to another. I know plastic is a good ...
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How can a glass rod become charged if it is an insulator?

I was reading some of the other questions, and I found this one about a glass rod and how it gains a net charge when rubbed with a silk scarf. I learned from working in a shop one summer that most ...
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Capacitor-like-thing for controlling temperature of fluid?

I want to minimise the Gibbs' phenomenon like thing i.e. sudden peaks (temperature peaks here) in a container. Assume you have a cone where you want to block the transmittance of the temperature into ...
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Why is more intrinsic carriers bad for high temperature semiconductors?

I'm taking a solid state course, and is currently on the subject of dielectrics. In one of the sections, concerning "Impurities in Dielectrics" the books says: "Impurities can also be used to make ...
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Does all electrical insulator can be electrostatically charged?

Does all electrical insulator can be electrostatically charged, or insulator with only dielectric property can? Thank you.
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301 views

Question about liquid / gaseous insulators

I'm looking for information about liquid / gaseous insulators, but I can't find any, is there any website (because I can't find on Wikipedia) where I can get this information? Also, can I get a list ...
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102 views

Single directional electric field insulator?

Is there any material, (kind of like a one way mirror), which allows an Electric Field to pass through from one direction, but not from the other? Thanks. Edit: As Ali has pointed out, one way ...
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insulator based gauss law questions

My book is incredibly scarce on insulator based Gauss law questions. Conductors seem to handle themselves pretty simply. Here's a question I'm working on that isn't part of my book. where the radii ...
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Magnetic field insulators

I was wondering if there is any way to stop the magnetic field, without having the insulator turned into magnet. Let me present this as a simple case, there is a magnet to the left and a piece of iron ...
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Spin Liquid in a band insulator?

In the literature, spin liquids are only possible in Mott insulators, however, I'm not entirely sure why the nuclear spin can't create a spin liquid in a band insulator. Is this possible? If so, is ...
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Grounding insulative material

When grounded, can an insulative material keep its charge for any measurable length of time? Or, I suppose, if it was a perfect insulator, would it discharge at all? An example might be a charged ...