Question

what is relative refractive index and absolute refractive index.....??????anyone

Answer 1

r indicating the speed of light in a given medium as either the ratio of the speed of light in a vacuum to that in the given medium (absolute index ofrefraction) or the ratio of the speed of light in a specified medium to that in the given medium (relative index ofrefraction) Symbol: n.

Answer 2

absolute refractive index is defined as a ratio of the speed of light in the vacuum and in selected medium  

relative refractive index is defined as a ratio of speed of light in two different media

When in relative refrective index ,second medium is vacuum then both will be same