What is Relative permittivity: Definition and 23 Discussions

The relative permittivity, or dielectric constant, of a material is its (absolute) permittivity expressed as a ratio relative to the vacuum permittivity.
Permittivity is a material's property that affects the Coulomb force between two point charges in the material. Relative permittivity is the factor by which the electric field between the charges is decreased relative to vacuum.
Likewise, relative permittivity is the ratio of the capacitance of a capacitor using that material as a dielectric, compared with a similar capacitor that has vacuum as its dielectric. Relative permittivity is also commonly known as the dielectric constant, a term still used but deprecated by standards organizations in engineering as well as in chemistry.

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  1. K

    Relative Permitivity of Black Paint | Hi Thank You!

    Hi i want to know what is the relative permitivity value of black paint. Thank you.
  2. qnach

    Connection between relative permittivity and bandwidth

    What is the connection of relative permittivity and bandwidth of an antenna? Higher relative permittivity resulted in high wider bandwidth?
  3. Jordan M

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  4. A

    How charge density of plate is changed by permittivity

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  5. A

    High K material in High frequency

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  6. W

    I Data needed: Relative permittivity of air

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  7. L

    Interpret current density in plasma as material property?

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  8. D

    Do the Relative Permittivity and Refractive Index of Water Match Up?

    Many textbooks and online sources give the relative permittivity of water as about 80 and the refractive index as 1.33. If you use the definition of refractive index to find the speed of light in water, you will find v = c/n ~ 2.56e8 m/s. However, if you use the equation to find the speed of...
  9. naiasetvolo

    Why do we multiply permittivity of vacuum with relative permittivity?

    Why do we multiply permittivity of vacuum with relative permittivity? What does this calculation mean?
  10. J

    How Should Relative Permittivity Be Applied in Electric Field Calculations?

    Homework Statement I've been given a question where I have to find the electric field strength at a point between two charges. Now I understand the mathematics but the question I'm trying to solve says two point charges of value 2C and 3C are position within a medium of relative permittivity...
  11. R

    Relative permittivity of a semiconductor material

    http://physics.stackexchange.com/questions/156708/can-the-relative-permittivity-of-a-semiconductor-material-be-lower-than-1 To measure the relative permittivity of a p-type semiconductor material (a metal phthalocyanine ) , a M-S-M structure was made by thermal evaporation method. The...
  12. F

    How Can Relative Permittivity Be Measured in the Stratosphere?

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  13. T

    Find the relative permittivity

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  14. A

    Relative Permittivity: Exploring Static Charge & Capacitance

    Hello forum members, I am trying to wrap my head around the concept of relative permittivity. I have read the Wikipedia article on the subject, but I don't feel quite satisfied. As far as I understand it, RP is essentially a measure of how well a given material holds a static charge relative to...
  15. M

    Change of relative permittivity of liquid and solid water

    Dear Physics Forum Users Commonly, the relative permittivity of liquid water is reported to be \epsilon_r = 78.0\epsilon_0, \epsilon_0 being the dielectric constant of the vacuum. For ice (solid water), \epsilon_r = 4 \epsilon_0 (heard it in a talk once). Is it correct to interpret the...
  16. X

    Can there be a material with relative permittivity < 1?

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  17. K

    How to compute complex relative permittivity

    Greetings. I don't know how to use an equation with a complex frequency term, specifically this one (aka Debye expression) for frequency-dependent permittivity: epsilon(omega) = epsiloninfinity + delta-epsilon/(1 + j*omega*tau) where epsilon(omega) is the permittivity at omega angular...
  18. A

    Relative permittivity of a conductor

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  19. O

    Relative permittivity of vacuum aluminum interface?

    funny but I could not reach the info from net quickly.
  20. R

    Relative permittivity of gold at radio-frequencies

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  21. F

    Different dielectric material with different relative permittivity

    I am wondering how to different dielectric material with different relative permittivity behave when put together. Say i have two concentric sphere and the space between them is filled with a dielectric of relative permittivity A from the outer surface of the inner sphere to the mid point...
  22. I

    Relative Permittivity and Refractive Index

    in relating the index of refraction to the relative permittivity (dielectric constant/function). it is known that n = \sqrt{\epsilon_r} for optical frequencies (i.e. \mu_r=1. now this website http://hyperphysics.phy-astr.gsu.edu/Hbase/tables/diel.html#c1 gives the relative permittivity of...
  23. N

    Dielectrical constant / relative permittivity

    Hi! Im woundering if the relative permittivity in a capacitor is dependent on the level of charge in the capacitor? /Nikke.
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