Question

If thin prism having prism angle of $6^{\circ }$ gives a deviation of $3^{\circ }$, then the refractive index of prism material is :

• A. $1.3$
• B. $1.5$
• C. $1.0$
• D. $1.7$

Answer 1

The correct option is B $1.5$

deviation $\left(\delta \right)$ is given by

$\delta =(\mu -1)A$

where $\mu$ is refractive index

$A$ is angle of prism.

from given information $\delta =3^o;A=6^o$

$\Rightarrow 3=(\mu -1)6$

$\Rightarrow \mu =\frac{1}{2}+1=\frac{3}{2}=1.5$

$\Rightarrow \mu =1.5$