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Hi,
The speed of light is given c=1/√(ε_{0}μ_{0}) where ε_{0} is permittivity of vacuum and μ_{0} is vacuum permeability.
The permittivity and permeability of a material is given as ε=ε_{r}ε_{0} and μ=μ_{r})μ_{0} respectively where ε is absolute permittivity of the material and ε_{r} is relative permittivity of the material with respect to vacuum. The same goes for permeability.
The speed of light in water is given as 2.25×10^{8} m/s and in glass it is around 1.95×10^{8} m/s.
I assume that speed of light in a certain material could be stated as c=1/√(εμ).
It looks like one cannot write c=1/√(εμ) because as you can see and as was expected that calculated value of speed of light in glass is lager than that of water.
So, how do we really calculate the speed of light in a material using its permittivity and permeability values, or where am I going wrong with my calculation?
Thank you!
The speed of light is given c=1/√(ε_{0}μ_{0}) where ε_{0} is permittivity of vacuum and μ_{0} is vacuum permeability.
The permittivity and permeability of a material is given as ε=ε_{r}ε_{0} and μ=μ_{r})μ_{0} respectively where ε is absolute permittivity of the material and ε_{r} is relative permittivity of the material with respect to vacuum. The same goes for permeability.
The speed of light in water is given as 2.25×10^{8} m/s and in glass it is around 1.95×10^{8} m/s.
I assume that speed of light in a certain material could be stated as c=1/√(εμ).
It looks like one cannot write c=1/√(εμ) because as you can see and as was expected that calculated value of speed of light in glass is lager than that of water.
So, how do we really calculate the speed of light in a material using its permittivity and permeability values, or where am I going wrong with my calculation?
Thank you!
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