Question

Assertion $\left(A\right)$ : When an unpolarized light is incident on a glass plate at Brewster's angle, the reflected ray and refracted ray are mutually perpendicular.

Reason $\left(R\right)$ : The refractive index of glass is equal to the sine of the angle of polarization.

• A. Both ${}^{\prime }{A}^{\prime }$ and ${}^{\prime }{R}^{\prime }$ are true and ${}^{\prime }{R}^{\prime }$ is the correct explanation of ${}^{\prime }{A}^{\prime }$.
• B. Both ${}^{\prime }{A}^{\prime }$ and ${}^{\prime }{R}^{\prime }$ are true and ${}^{\prime }{R}^{\prime }$ is not the correct explanation of ${}^{\prime }{A}^{\prime }$.
• C. ${}^{\prime }{A}^{\prime }$ is true and ${}^{\prime }{R}^{\prime }$ is false.
• D. ${}^{\prime }{A}^{\prime }$ is false and ${}^{\prime }{R}^{\prime }$ is true.

Answer 1

The correct option is C ${}^{\prime }{A}^{\prime }$ is true and ${}^{\prime }{R}^{\prime }$ is false.


Brewster's law:
When an unpolarized light is incident on a glass plate at Brewster angle, the reflected ray becomes plane polarized and the refracted ray is partially polarized also the reflected and refracted ray are mutually perpendicular.

Also, $\mu =\tan i_P$

Where,
$\mu =$ refractive index of medium
$i_P=$ Brewster angle

Thus, $A$ is true, and $R$ is false

Hence, $\left(C\right)$ is the correct option.