Question

what is refractive index​
tell pleasee

Answer 1

Answer:

Refer to this attachment

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Answer 2

the ratio of the velocity of light in a vacuum to its velocity in a specified medium.

In optics, the refractive index of a material is a dimensionless number that describes how fast light travels through the material. It is defined as where c is the speed of light in vacuum and v is the phase velocity of light in the medium.