Question

speed of light in glass is 2×10^8 m/s. find the refractive index of the glass​

Answer 1

$\textbf{\huge\underline{\underline\red{solution} : - }} \\ \\ \textit{ \tt{The refractive index of a medium }} \\ \textit{ \tt{can be calculated using the }}\\ \textit{ \tt{following formula:}}\\ \textit{ \tt{</p><p></p><p> \red{ => n }}} \tt \red{= \frac{c}{v} }\\ \textit{ \tt{where}}\\ \textit{ \tt{ \red{n }is the refractive index of }}\\ \textit{ \tt{the medium}}.\\ \textit{ \tt{ \red{c }is the velocity of light }}\\ \textit{ \tt{in vacuum.}} \tt \purple{( 3 × {10}^{8} m/s)}\\ \textit{ \tt{</p><p></p><p> \red{v} is the velocity of light }}\\ \textit{ \tt{in the medium.}} \\ \\ \tt \underline\red{given } : - </p><p> \\ \\ \tt \red{c } \: of \: vacuum = 3 × {10}^{8} m/s \\ \tt \red{v} \: of \: glass = 2× {10}^{8} m/s \\ \tt \red{n} \: is \: refractive \: index = \: ? \\ \\ \tt \purple {by \: formula} \\ \tt \red{ = > n = \frac{c}{v } } \\ \\ \tt \purple{= > n = \frac{ 3 × \cancel{{10}^{8}} }{ 2 × \cancel{{10}^{8}} } = \frac{3}{2} = 1.5} \\ \\ \sf \blue {hence \: refractive \: index \: of \: glass \red{ \: n = \purple{1.5} }}$