Question

The refractive index of glass is $1.520$ for red light and $1.525$ for blue light. Let $D_1$, and $D_2$ be angles of minimum deviation for red and blue light respectively in a prism of this glass then,

• A. $D_1 < D_2$
• B. $D_1 = D_2$
• C. $D_1$ can be less than or greater than $D_2$ depending upon the angle of prism
• D. $D_1 > D_2$

Answer 1

Answer: (A)

$D_1 < D_2$

Answer 2

Given : $\mu_{R}=1.520$, $\mu_{B}=1.525$ As, $\mu=\frac{sin \left(\frac{A+D}{2}\right)}{sin \left(\frac{A}{2}\right)}$ where A is the angle of prism, D is the angle of minimum deviation Here, $\mu_{R}