Define the term, “refractive index” of a medium. Verify Snell’s law of refraction when a plane wavefront is propagating from a denser to a rarer medium. Solution
The factor by which speed of light gets reduced with respect to the “speed of light in vacuum” is said to be the refractive index for the medium.
`μ = c/ν or ν = c/mu`
Here v is the speed of light in the medium, c is the speed of light in vacuum and μ is the defined refractive index for the medium.