Multiple choice

What is the speed of light in the glass whose refractive index is 1.20? (Given: Speed of light in vacuum = 3 × 108 m/s)

  1. 3.6 x 108 m/s

  2. 2 x 108 m/s

  3. 0.4 x 10-8 m/s

  4. 0.8 x 108 m/s

  5. 0.4 x 108 m/s
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Speed of light in glass = Speed of light in vacuum/refractive index of glass
= 3 × 108/1.20 = 2.5 x 108 m/s

Keep practicing — related questions