Polarization at Brewster’s Angle – Rankers Physics

Miscellaneous: Practice Problem & Solution

Assertion (A): The plane of polarization of reflected ray is parallel to the refracting surface, when light is incident at polarising angle. Reason (R): Vibration of electric field in refracted ray ceases about plane parallel to refracting surface.  
Both (A) & (R) are true and the (R) is the correct explanation of the (A)
Both (A) & (R) are true but the (R) is not the correct explanation of the (A)
(A) is true but (R) is false
Both (A) and (R) are false

Short Solution (Best for NEET):

To solve this problem, we apply the core principles of Miscellaneous. Understanding the underlying formula is key to arriving at the correct answer below:

At the polarizing angle (Brewster's angle), the reflected light is completely plane-polarized with its electric field vibrations perpendicular to the plane of incidence (i.e., parallel to the refracting surface). Thus, A is true. The refracted ray is partially polarized and still has electric field vibrations in various planes, not ceasing in any specific plane. Thus, R is false.

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