Can a material have both dielectric and resistance properties?

In summary, materials can have both dielectric and resistance properties. This is important when high frequency AC is concerned and an insulating material (dielectric) is constantly being polarised in different directions.
  • #1
Apteronotus
202
0
Hi,

Do material posses both dielectric as well as resistance properties?

I imagine that when there is a difference in potential across a volume of some material, some current will flow (I=V/R <-- the material's resistance), but also the material may become polarized to a certain degree (dielectric property). Is this true? Am I on the right track?

Thanks,
 
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  • #2
Apteronotus said:
Hi,

Do material posses both dielectric as well as resistance properties?

I imagine that when there is a difference in potential across a volume of some material, some current will flow (I=V/R <-- the material's resistance), but also the material may become polarized to a certain degree (dielectric property). Is this true? Am I on the right track?

Thanks,

Yes, the two are important, taken together in some materials. This is particularly important when high frequency AC is concerned and an insulating material (dielectric) is constantly being polarised in different directions. Take, for instance, a cheap Capacitor that works fine at 1MHz. The 'resistive' component of the dielectric can produce serious losses at 100MHZ or higher. (But I think this is the 'inverse' of your actual question.)
Where DC is concerned, the valence electrons in a metal will move readily, so the electric field will be small - and, hence, the other electron orbitals will not be altered significantly (which is what is implied by 'polarisation'). In semiconductors or some impure mixtures, the internal fields when conducting DC could be enough to produce some distortion of the molecules but it would be very difficult to detect this effect at DC.
The idea of this complex dielectric constant is essentially something relevant to AC.
 
  • #3
And yes from my location as well. Sophiecentaur and I seem to live in places where laws of physics show great similarities.

One example: very pure water is used for a limited time as a dielectric, to store amazing amounts of energy. It was done in the previous version of the Z-machine (have a search, it's fun) because water has a very good breakdown field over a short time and a huge permittivity around 80, making capacitors compact. It's also cheap enough to fill a complete pool, even when de-ionized, so said capacitor, charged at several MV, makes a really nice ZAP.

But if someone tries to keep the charge for too long, then the resistance (the conductivity) gets annoying and discharges the water capacitor.
 
  • #4
Thank you both. :)
 
  • #5


I can confirm that it is possible for a material to have both dielectric and resistance properties. In fact, many materials exhibit both of these properties simultaneously. This is because the two properties are related but different measures of a material's response to an electric field.

Resistance, as you mentioned, is a measure of how easily a material allows current to flow through it. This is determined by the material's atomic and molecular structure, as well as its conductivity. On the other hand, dielectric properties refer to a material's ability to store and respond to an electric field. This is related to the material's polarization and permittivity.

Some materials, such as semiconductors, exhibit both high resistance and dielectric properties. In these materials, the movement of electrons is restricted, leading to high resistance, but they also have the ability to store and respond to electric fields, making them good dielectrics. Other materials, such as ceramics and certain polymers, also possess both properties to varying degrees.

So, in short, you are on the right track. A material can indeed have both dielectric and resistance properties, and it is common for many materials to exhibit both simultaneously. I hope this helps clarify your understanding of these properties.
 

What is the difference between a dielectric and a resistor?

A dielectric is a material that can store electric charge, while a resistor is a material that restricts the flow of electric current. In other words, a dielectric is an insulator, while a resistor is a conductor.

How do dielectrics and resistors affect electric circuits?

Dielectrics are commonly used in capacitors to store electric charge, while resistors are used to control the flow of current in a circuit. Both components play important roles in regulating the flow of electricity in a circuit.

What are some examples of dielectrics and resistors?

Common examples of dielectrics include glass, rubber, and plastic, while resistors can be made of materials such as carbon, metal, or ceramic. Both types of components can also be found in various electronic devices and appliances.

Which component is more important in an electric circuit, a dielectric or resistor?

Both dielectrics and resistors are essential components in an electric circuit, and their roles cannot be compared in terms of importance. Each serves a specific purpose in regulating the flow of electricity and ensuring the proper functioning of the circuit.

Can a material be both a dielectric and a resistor?

Yes, some materials can exhibit both dielectric and resistive properties. This is known as a "semi-conductor" and is commonly used in electronic devices such as transistors and diodes.

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