Q8 of 27 Page 383

What is the Brewster angle for air to glass transition? (Refractive index of glass = 1.5.)

Brewster’s angle is angle of incidence of light on a refracting surface for which refracted and reflected light are linearly polarised. They are also perpendicular to each other.


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According to Brewster’s law when angle of incidence is Brewster angle, say θB,


tan(θB) = μ


where μ is refractive index of the refracting medium


i.e., tan(θB) = 1.5


θ = tan-1(1.5)


= 56.3°


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