Dear all,(adsbygoogle = window.adsbygoogle || []).push({});

i am a bit confused with a very simple equation connecting refractive index of water and its dielectric constant for visible range of wavelengths and room temperature. :grumpy:

i hope, You can help me

as we know, the refractive index 'n' can be defined as

n=sqrt(epsilon*mu), (http://en.wikipedia.org/wiki/Refractive_index)

where 'epsilon' is material's dielectric constant (or material's relative permittivity) and 'mu' is its relative permeability.

for water we have:

mu is almost 1, epsilon=80 (http://en.wikipedia.org/wiki/Dielectric_constant)

it means that (using the equation above) the refractive index of water is n=sqrt(80)=8.94, but the measured refractive index of water at room temperature is about 1.33 (http://www.ps.missouri.edu/rickspage/refract/refraction.html, http://www.cargille.com/certwater.shtml) [Broken].

Thus, refractive index computed from the equation is not the same and not near to its experimental quantity.

Where is my fault?

Thanks

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# Optics: refractive index and dielectric constant

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