Question

(a) Define absolute refractive index
ne absolute refractive index and express it mathematically.
b) Study the following ray diagram and list two mistakes committed by
the student while tracing it. Rectify these mistakes by drawing the
correct ray diagram to show the real position and size of the image
corresponding to the position of the object AB.
​

Answer 1

Answer:

ratio of velocity of light in medium and in vaccum is called absolute refractive index

Answer 2

Absolute refractive index: Absolute refractive index is defined as the ratio of velocity of light in vacuum to velocity of light in medium.

Mathematically, it can be written as

                   n = c/v

Errors in given ray diagram:

• The first error in the ray diagram is that the position of image is wrong. In this case when the object is placed between $F_{1}$ and $2F_{1}$, the image is formed beyond $2F_{2}$.
• The second error is that of image size. The image formed here must be enlarged.