# Numerical problems on the refractive index of a medium – from class 10 Light chapter

In this post, we will solve a bunch of Numerical problems on the refractive index of light. The refractive index is written as RI as well.

Numerical problems on the refractive index

1 ] The speed of light in air is 3 x 10^8 m/s and in glass it is 2×10^8 m/s. The RI of glass is ________________.

Solution: RI of glass = speed of light in air /speed of light in glass = (3 x 10^8)/(2 x 10^8) = 1.5

2 ] The speed of light in water is 2.25 x 10^8 m/s. So the RI of water is:

Solution: air µwater = C /V = speed of light in air / speed of light in water = ( 3 x 10^8) / (2.25 x 10^8) =1.33

3 ] The RI of the diamond is 2.41. What is the speed of light in a diamond?

Solution: RI of diamond = speed of light in air /speed of light in diamond
=> µdiamond =C / Vdiamond
=> Vdiamond = C / µdiamond = (3 x 10^8) / 2.41 m/s = 1.24 x 10^8 m/s

4 ] Refractive index(RI) of glass is 1.5 and that of water is 1.33.
What is the RI of glass with respect to water?
What is the RI of water with respect to glass?

Solution: Refractive index(RI) of glass (µglass)is 1.5
and Refractive index(RI) of water(µwater) is 1.33
Now, RI of glass with respect to water = waterµglass = µglass / µwater = 1.5 /1.33 = 1.127

RI of water with respect to glass = glassµwater = µwater / µglass = 1.33/1.5 = 0.89

Numerical problems on the refractive index of a medium – from class 10 Light chapter