Question

Light travels with a velocity 1.5×10^8 m/s in a medium. On entering second medium its velocity becomes 0.75×10^8 m/s. What is the refractive index of the second medium with respect to the first medium?

Answer 1

let 1.5x10^8m/s be the velocity of light in first medium (V1)
and 0.75x10^8m/s be the velocity of light in second medium(V2)
therefore,
2n1=V1/V2
=1.5x10^8/0.75x10^8
=0.75/1.5
=10/3
Hence,the refractive index of the second medium with respect to first medium is 10/3