Question

Light enters from air to glass having refractive index 1.50. What is the speed of light in the glass? The speed of light in vacuum is 3 x 108 ms-1.

Answer 1

Light enters from air to glass having refractive index 1.50. What is the speed of light in the glass? The speed of light in vacuum is 3 x 108 ms-1.

Answer-

Refractive index of a medium (nm) = Speed of light in vacuum/Speed of light in the medium

Speed of light in vacuum (c) = 3 × 108 m/s

Refractive index of glass (ng) = 1.50

Speed of light in the glass (v) = Speed of light in vacuum/ Refractive index of glass

= c/ng

=3 × 108/1.50 = 2x 108 ms-1.

Answer 2

Answer:

$\blue{✎﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏}$

$\pink{Given\: that:-}$

Speed of light in Vacuum,

$\sf c = 3 \times {10}^{8} ms$

$\purple{Formula:-}$

$\sf Refractive\: index \:of\: a \:medium = \dfrac {Speed\: of \:light\: in\: the \:vacuum}{Speed\: of \:light\: in \:the \:medium}$

$\red {Solution:-}$

Speed of light in the glass =

$\begin{gathered}\\ : \implies \sf \: \dfrac {Speed \:of\: light\: in \:the\: vacuum}{Refractive\: index \:of \:a \:glass} \\ \\\end{gathered}$

$\begin{gathered}\\ : \implies \sf \: \dfrac {3 \times {10}^{8} }{1.50} \\ \\\end{gathered}$

$\begin{gathered}\\ : \implies \sf \: {2 \times {10}^{8} {ms}^{-1}}\\ \\\end{gathered}$

$\green{✎﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏}$