The refractive index and the permeability of a medium are respectively 1.5 and `5xx10^-7Hm^-1`. The relative permittivity of the medium is nearly

Options

A. 25
B. 15
C. 10
D. 6

Answer

D

Explanation

Refractive index, `n=(c)/(v)`
or `v=(c)/(n)=(3xx10^(8))/(1.5)=2xx10^(8)"m s"^(-1)`
Here, `mu=5xx10^(-7)"H m"^(-1)`
`therefore" "v=(1)/(sqrt(muepsilon))=(1)/(sqrt(muepsilon_(0)epsilon_(r)))`
`epsilon_(r)=(1)/(v^(2)muepsilon_(0))=(1)/((2xx10^(8))^(2)xx(5xx10^(-7))xx(8.85xx10^(-12)))`
`=5.65~=6`