Question

An unpolarized light incident on a plane glass surface gets totally polarized on reflection. If the refractive index of glass is $\tan 57^{\circ}$, then the angle of refraction is:

• A. $90^{\circ}$
• B. $33^{\circ}$
• C. $13^{\circ}$
• D. $37^{\circ}$
• E. $45^{\circ}$

Hint:

Angle of incidence + Angle of refraction = $90^{\circ}$ at Brewster's angle.

Answer 1

The Correct Option is B

Step 1: Concept
According to Brewster's Law, total polarization occurs when $\mu = \tan i_p$, where $i_p$ is the polarizing angle.

Step 2: Analysis
Given $\mu = \tan 57^{\circ}$, the polarizing angle $i_p = 57^{\circ}$.

Step 3: Calculation
At the polarizing angle, the reflected and refracted rays are perpendicular: $i_p + r = 90^{\circ}$.
$r = 90^{\circ} - 57^{\circ} = 33^{\circ}$. Final Answer: (B)