State the laws of refraction of light. If the speed of light in vacuum is 3X108 ms-1, find the speed of light in a medium of absolute refractive index 1.5.
Laws of refraction of light: First law : The incident ray, the refracted ray, and the normal at the point of incidence all line in the same plane. Second law (Sell's law): The ratio of sine of angle of incidence to the sine of angle of refraction is a constant for a given pair of media. i.e,. sinrsini=Constant Speed of light in vacuum, c=3×108 m/s Speed of light in medium, v=1.4×108 m/s Absolute refractive index = Speed of light in mediumSpeed of light in vacuum =1.4×108m/s3×108m/s=2.14
