Q. A ray of light strikes a glass plate at an angle of $60^{\circ}$. If the reflected and the refracted rays are perpendicular to each other the refractive index of glass is

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A

$\sqrt{3} / 2$

B

$3 / 2$

C

$1 / 2$

D

$\sqrt{3}$

Solution:

at polarising angle of incidence
$n=\tan { }_{p}=\sin { }_{p} / \sin r=\tan 60^{\circ}=\sqrt{3}$

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