Q2 of 47 Page 1

When unpolarised light is incident on the interface separating the rarer medium and the denser medium, Brewster angle is found to be 60°. Determine the refractive index of the denser medium.


Brewster angle (θp) is given to be 60˚.


Brewster law states that the tangent of the polarising angle of incidence (Brewster angle) of a transparent medium is equal to the refractive index of the medium.


Mathematically,


Where, =Brewster’s angle


=relative refractive index of denser medium with respect to rarer medium


Now,


(since the medium is air)




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