Question

Velocity of light in air is 3* 10^8 m/ s . While its velocity in a medium is 1 5. / 10^8 m /s . Then, refractive index of this medium is

Answer 1

N =(3 × 10^8)/(0. 3 × 10^8). N = 10. It's is a ratio of 2 similar quantities( velocity) because refractive index has no units.