White light is incident on one of the refracting surfaces of a prism of angle 5°. 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

Question

White light is incident on one of the refracting surfaces of a prism of angle 5°. 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° (B) 0.09° (C) 1.8 ° (D) 1.2 °

Tardigrade Admin · Accepted Answer

Angular dispersion, δb-δr =(μb-μr) A =(1.659-1.641) 5° =0.09°

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

$0. 9^{\circ}$

$0.0 9^{\circ}$

$1. 8^{\circ}$

$1. 2^{\circ}$

Angular dispersion,
$δ_{b} - δ_{r} = (μ_{b} - μ_{r}) A$
$= (1.659 - 1.641) 5^{\circ}$
$= 0.0 9^{\circ}$

Q. White light is incident on one of the refracting surfaces of a prism of angle 5∘. 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

0.9∘

0.09∘

1.8∘

1.2∘