Bala J's answer to jawaria waseem's United States question.

done {{ upvoteCount }} Upvotes
clear {{ downvoteCount * -1 }} Downvotes
Bala J
Bala J's answer
65 answers (Tutor Details)
1st
Index of refraction or refractive index is a ratio of speed of light in vaccum to the speed of light in a material/medium