Ask
Login
1
3.5kviews
minimum refractive index of prism
written 8.4 years ago by gravatar for teamques10 teamques10 ★ 68k •   modified 8.4 years ago

A 45° - 45° - 90° prism is immersed in alcohol (n = 1.45). What is the minimum refractive index the prism must have if a ray incident normally on one of the short faces is to be totally reflected at the long face of a prism?

Mumbai University > Electronics and Telecommunication > Sem7 > Optical Communication and Networks

Marks: 5M

Year: May 2012
optical networks
ADD COMMENT EDIT
1 Answer
1
448views
written 8.4 years ago by gravatar for teamques10 teamques10 ★ 68k •   modified 8.4 years ago

Given: $θ_c$= 45°

$n_1$ = 1.45

To find: refractive index $n_2$

Solution:

enter image description here

$θ_c= sin^{-1} \frac{ n_2}{n_1} $

$sin^{-1} \frac{n_2}{n_1}$ = 45°

$\frac{n_2}{n_1}$ = sin 45 = 0.707

$n_{2}$ = 1.45 * 0.707

= 1.025

$n_2$= Minimum refractive index= 1.025

$$\boxed{Minimum \ \ \ refractive \ \ \ index(n_2)= 1.025}$$
ADD COMMENT EDIT
Please log in to add an answer.