On entering in a medium from air, the speed of light becomes half of its value in air. Find the refractive index of that medium with respect to air?
Refractive Index of a medium (µ) = Velocity of light in vacuum / Velocity of light in the medium
Let the velocity of light in vacuum be v1 and velocity of light in the medium be v2.
v1/2 = v2
Hence, µ = v1/v2