The polarising angle for a medium is found to be $60^{\circ}$. The critical angle of the medium is
- $\sin^{-1}\left(\frac{1}{2}\right) $
- $\sin^{-1}\left(\frac{\sqrt{3}}{2}\right)$
- $\sin^{-1}\left(\frac{1}{\sqrt{3}}\right)$
- $\sin^{-1}\left(\frac{1}{4}\right) $
The Correct Option is C
Solution and Explanation
The refractive index of the medium is given by
$n=\tan i_{p}$
where $i_{p}=$ polarising angle
$\Rightarrow n=\tan 60^{\circ}$
$\Rightarrow n=\sqrt{3}$
If $C$ be the critical angle for the medium, then
$ n =\frac{1}{\sin C} $
$\sin C =\frac{1}{n}=\frac{1}{\sqrt{3}} $
$ C =\sin ^{-1}\left(\frac{1}{\sqrt{3}}\right)$
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Polarisation
Light travels in form of transverse EM waves. The underlying oscillation is along directions perpendicular to the propagation direction, in this example, oscillating electric and magnetic fields. Process of restricting the vibration of light waves to one direction is known as Polarisation.
Types of Polarisation:
There are three types of polarisation such as:
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- Elliptical Polarisation: In this, both the phase difference and amplitude between the two linear components are not equal.
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Methods of Polarisation of Light:
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- Polarization by Refraction
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