A certain material has refractive indices 1.56, 1.60 and 1.68 for red, yellow and violet light respectively. (a) Calculate the dispersive power. (b) Find the angular dispersion produced by a thin prism of angle $6^{\circ}$ made of this material.

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Solution

Given that : $μ_{r}$ = 1.56,

$μ_{y}$ = 1.60, and $μ_{v}$ = 1.68

(a) Dispersive power = $ω$

$= \frac{μ_{v} - u_{r}}{μ_{y} - 1} = \frac{1.68 - 1.56}{1.60 - 1} = \frac{0.12}{0.60} = 0.2$

(b) Angular dispersion $= (μ_{r} - μ_{r}) a$

$= (0.12) \times 6^{\circ} = {0.72}^{\circ}$

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A certain material has refractive indices 1.56, 1.60 and 1.68 for red, yellow and violet light respectively. (a) Calculate the dispersive power. (b) Find the angular dispersion produced by a thin prism of angle 6∘ made of this material.

Given that : μr = 1.56, μy = 1.60, and μv = 1.68 (a) Dispersive power = ω =μv−urμy−1=1.68−1.561.60−1=0.120.60=0.2 (b) Angular dispersion =(μr−μr)a =(0.12)×6∘=0.72∘

A certain material has refractive indices 1.56, 1.60 and 1.68 for red, yellow and violet light respectively. (a) Calculate the dispersive power. (b) Find the angular dispersion produced by a thin prism of angle $6^{\circ}$ made of this material.

Given that : $μ_{r}$ = 1.56,

$μ_{y}$ = 1.60, and $μ_{v}$ = 1.68

(a) Dispersive power = $ω$

$= \frac{μ_{v} - u_{r}}{μ_{y} - 1} = \frac{1.68 - 1.56}{1.60 - 1} = \frac{0.12}{0.60} = 0.2$

(b) Angular dispersion $= (μ_{r} - μ_{r}) a$

$= (0.12) \times 6^{\circ} = {0.72}^{\circ}$