Dielectrical constant / relative permittivity

Thread starter nikkebargell
Start date Mar 21, 2007
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Constant Permittivity Relative Relative permittivity

AI Thread Summary

The discussion focuses on the relationship between relative permittivity and charge levels in capacitors. It is noted that while the charge affects the electric field through the dielectric, in an ideal capacitor, permittivity remains constant regardless of the field. However, real capacitors exhibit some nonlinearity, particularly at high voltages, which can lead to breakdown. The conversation confirms the initial understanding that relative permittivity is generally independent of charge in ideal conditions. Overall, the nuances of dielectric behavior in practical applications are acknowledged.

Mar 21, 2007

nikkebargell

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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Mar 21, 2007

Dick

Science Advisor

Homework Helper

The charge on the capacitor affects the E field through the dielectric. In an ideal capacitor the permittivity is independent of field. Real devices have some degree on nonlinearity (eg at high voltages they will simply break down).

Mar 21, 2007

nikkebargell

ok cool, that's what i thought.

cheers

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