# The refractive index of a material changes by

Question:

The refractive index of a material changes by $0.014$ as the colour of the light changes from red to violet. A rectangular slab of height $2.00 \mathrm{~cm}$ made of this material is placed on a newspaper. When viewed normally in yellow light, the letters appear $1.32 \mathrm{~cm}$ below the top surface of the slab. Calculate the dispersive power of the material.

Solution: