Question

Light travels with a velocity 1.5 x 10⁸ m/s in a medium. On entering second medium its velocity becomes 0.75 x 10⁸  m/s. What is the refractive index of the second medium with respect to the first medium?

Answer 1

Given :
Velocity of light in a first medium = V₁ = 1.5 x 10⁸ m/s
Velocity of light in second medium = V₂ = 0.75 x 10⁸ m/s
Refractive index of second medium = ₂n₁ = ?
                                                   ₂n₁ = `V_1/V_2`
                                                ₂n_1 `= (1.5 x10^8)/(0.75 xx 10_8`
                                                        = 2

Hence, the refractive index of second medium with respect to first medium is 2.