Light enters from air to glass having refractive index 1.50. What is the speed of light in the glass? The speed of light in vacuum is 3 × 108 m s–1.

Q. Light enters from air to glass having refractive index 1.50. What is the speed of light in the glass? The speed of light in vacuum is 3 × 108 m s–1.

 

Answer:-

Given, speed of light in vacuum C = 3 × 108 m s–1
Refractive index of glass ng = 1.50
Speed of light in the glass vg = ?

C
ng =
Vg
3 × 10 8
ng =
Vg
3 × 10 8
1.5 =
Vg
3 × 10 8
Vg =
1.5
Vg = 2 × 108 ms−1

Speed of light in the glass vg = 2 × 108 ms−1