Q. White light is incident on one of the refracting surfaces of a prism of angle $5{^\circ}.$ If the refractive indices for red and blue colours are 1.641 and 1.659 respectively, the angular separation between these two colours when they emerge out of the prism is
A) $0.9{^\circ}$
B) $0.09{^\circ}$
C) $1.8{^\circ}$
D) $1.2{^\circ}$
Explanation
(b) Angular description,
$\delta_{b} - \delta_{r} = \left( \mu_{b} - \mu_{r} \right)A$
$= (1.659 - 1.641)5{^\circ}$
$= 0.09{^\circ}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.