Question

The refractive indices of violet and red light are $1.54$ and $1.52$ respectively. If the angle prism is $100$ , then the angular dispersion is :

• A. $0.02$
• B. $2$
• C. $3.06$
• D. $30.6$

Answer 1

Answer: (B)

$2$

Angular dispersion is given as,

$\alpha =\left({\mu }_V-{\mu }_R\right)A$

$\alpha =\left(1.54-1.52\right)\times 100$

$\alpha =0.02\times 100$

$\alpha =2$

Thus, angular dispersion is $2{}^{\circ }$.