Define absolute refractive index of a medium. Light enters from air to water having refractive index `4/3` . Find the absolute refractive index of a medium if the speed of light in vacuum is `3xx10^(8)` m/s.

Explanation

Absolute refractive index of a medium
`=("Velocity of lgiht in vacuum")/("Velocity of light in medium")`
`v=c/n=(3x10^(8))/4=2.25xx10^(8)m//s`