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## Class 10 Physics (India)

### Course: Class 10 Physics (India)>Unit 1

Lesson 9: Absolute & relative refractive index

# Relative & absolute R.I. connection

Let's find an expression between the relative refractive index and absolute refractive index. Created by Mahesh Shenoy.

## Want to join the conversation?

• What does the C represent again?
• The speed of light in vacuum/air. It's a universally recognized constant, made famous through Einstein's equation E=mc²
• can we also do it like, find the velocities of glass and water separately, and then do Ngw = x
Vg = Vw/x
x = Vw/Vg
x = 2.25 * 10^8 / 2 * 10^8

x=1.125
(1 vote)
• Timestamp:
We can also use 1/1.33 as 3/4 because 1.33 = 4/3,
So 1/(4/3)=1*3/4= 3/4.
It just makes the calculation simpler
(1 vote)
• shouldn't it be n12= n2/n1?
(1 vote)