Question

the speed of the light in liquid is 1.2 ×10 ki power 8 m/s .what is the refractive index of the liquid?

Answer 1

refractive index of liquid = speed of light in air / speed of light in liquid
                                       = 3 x 10^8 / 1.2 x 10^8
                                       = 3/1.2 = 30/12 = 5/2
refractive index is ratio of two like quantities so it doesn't have units
therefore refractive index of liquid is 2.5