Question

what do you mean by the line, ' the refractive index of glass is 1.5'?

Answer 1

Explanation:

The speed of light is glass is 1.5 times slower than the speed of light in air/vacuum

Answer 2

Answer:

The refractive index of glass is 1.5 for white light means that the speed of white light in air is 1.5 times the speed of light in glass