Question

what is absolustic refractive index ​

Answer 1

the ratio of speed of light in a medium to the speed of light in vaccum is termed a it's absolutic refractive index.

Rm= Sa/Sm

Answer 2

Absolute refractive is the velocity of light in vaccum with respect to the velocity of light in the given medium

$\rm n = \frac{Velocity\:of\:light\: in vacumm \:(c)}{Velocity\:of\:light\: in\: the\: given \:medium\:(v)}$