In this lesson can you explain me the formula n21 = speed of light in medium1 / speed of light - Science - Light - Reflection and Refraction

Question

In this lesson can you explain me the formula n21 = speed of
light in medium1 / speed of light in medium 2

Ankur · Accepted Answer

1μ2 = μ2μ1 = cv2cv1 = v1v2where, c is speed of light in vacuum and v is the speed of light in respective medium

In this lesson can you explain me the formula n21 = speed of light in medium1 / speed of light in medium 2