the refractive index changes with the colour of the light leading to depresion . if the refractive index for blue light in a certain glass is 1.639 and red light is 1.621 .calculate the value of angle refraction in both the rays? (sin50°=0.7660)
Answers
Answer:You have it backward, faster speed of light in a material corresponds to less refraction, not more. In the limit that the speed of light in a material was the same as the speed of light in vacuum, there would be no refraction at all.
It can be shown that in a material the index of refraction is the speed of light in vacuum, c divided by the speed of light in the material cm.
n=ccm
So, slower speed in a material corresponds to a larger index of refraction ,and higher speed to a lower index of refraction. The index of refraction is always greater than or equal to 1, because c, the speed of light in vacuum, is always greater than the speed in a material.
So, as you have stated, red light has a lower index of refraction than blue light since it also has a shorter wavelength, so lower index of refraction corresponds to higher speed in a material.