The dielectric constant of water is 80, but refractive index

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Discussion Overview

The discussion revolves around the relationship between the dielectric constant and the refractive index of water, specifically questioning the validity of the expression n*n=ε. Participants explore the implications of frequency dependence on these values and consider potential explanations for the observed discrepancy.

Discussion Character

  • Debate/contested

Main Points Raised

  • One participant notes that the dielectric constant of water is 80 while its refractive index is 1.33, questioning the validity of the expression n*n=ε.
  • Another participant emphasizes that both the dielectric constant and the refractive index are frequency dependent, suggesting the need for values measured at the same frequency.
  • A participant mentions that the question is part of an exam with multiple-choice options, proposing that option (3) - that the two quantities are measured by different experiments - is likely correct.
  • A later reply indicates that the thread should be moved to a homework forum for proper categorization.

Areas of Agreement / Disagreement

Participants express differing views on the relationship between the dielectric constant and refractive index, with no consensus reached on the validity of the expression or the correct explanation for the discrepancy.

Contextual Notes

The discussion highlights the potential limitations of the relationship due to frequency dependence and the context of measurement, but does not resolve these issues.

pallab
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The dielectric constant of water is 80, however its refractive index is 1 ·33 invalidating
the expression n*n=ε. why?
 
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Dielectric constant and n are frequency dependent. Are you sure you got values at the same frequency?
 
Khashishi said:
Dielectric constant and n are frequency dependent. Are you sure you got values at the same frequency?
No.
Actually it is a exam question with 4 options, given below-
(1) the water molecule has no permanent dipole moment
(2) the boiling point of water is 100 °C
(3) the two quantities arc measured by different experiments
(4) water is transparent to visible light

It seems that option (3) is correct .
what do you think?
 
This will have to be posted in a homework forum, with the template properly filled out.

Thread closed.
 

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