Question

The Brewster angle for the glass-air interface is $53.74^{\circ} .$ If ray of light going from air to glass strikes at an angle of incidence $45^{\circ},$ then the angle of refraction is (tan $\left.53.74^{0} \approx \sqrt{2}\right)$

• A. $60^{\circ}$
• B. $30^{\circ}$
• C. $25^{\circ}$
• D. $54.74^{\circ}$

Answer 1

Answer: (B)

According to the Brewster $\mu=\tan i _{ p }$
$\mu=\tan 53.74$
$ \mu=\sqrt{2}$
$\therefore \sqrt{2}=\frac{\sin i}{\sin r}$
$ \Rightarrow \sqrt{2}=\frac{\sin 45^{\circ}}{\sin r}$
$\sin r=\frac{1}{\sqrt{2}} \times \frac{1}{\sqrt{2}}=\frac{1}{2}$
$r=\sin ^{-1}\left(\frac{1}{2}\right)$
$r=30^{\circ}$