Question

A prism ($\mu =\sqrt{3}$) of refracting angle 30${}^{\circ }$ is coated with a thin film of transparent material of refractive index 2.2 on face AC of the prism. A light of wavelength 6600A${}^{\circ }$is incident on face AB such that angle of incidence is 60${}^{\circ }$, then angle of emergence is

• A. 0${}^{\circ }$
• B. 90${}^{\circ }$
• C. 60${}^{\circ }$
• D. 30${}^{\circ }$

Answer 1

Answer: (A)

0${}^{\circ }$

From Snells law we have,
$1\times sin{60}^o=\sqrt{3}sin{r}_1$
$⟹r_1={30}^o$
From $A=r_1+r_2$
$⟹r_2=0^o$
Therefore, $i_2=0^o$