Question

 A ray of light travels from one medium of refractive index 1.2 to a medium of refractive index 1.6 what is the ratio of velocity of light in first medium to velocity of light in second medium

Answer 1

Given:

A ray of light travels from one medium of refractive index 1.2 to a medium of refractive index 1.6.

To find:

Ratio of Velocity of light in 1st medium to 2nd medium?

Calculation:

• We know that refractive index $(\mu)$ is defined as ratio of velocity of light in vacuum to velocity of light in that medium.

Taking corresponding ratios :

$\rm \: \dfrac{ \mu1}{ \mu2} = \frac{ \bigg( \dfrac{ v_{vacuum}}{v_{1}} \bigg)}{\bigg( \dfrac{ v_{vacuum}}{v_{2}} \bigg)}$

$\rm \implies \: \dfrac{ \mu1}{ \mu2} = \dfrac{ v_{2} }{ v_{1} }$

$\rm \implies \: \dfrac{ \mu2}{ \mu1} = \dfrac{ v_{1} }{ v_{2} }$

$\rm \implies \: \dfrac{ v_{1} }{ v_{2} } = \dfrac{1.2}{1.6}$

$\rm \implies \: \dfrac{ v_{1} }{ v_{2} } = 0.75$

So, ratio of velocity in the media is 0.75 .