i > C . i.e. \sin C" class="fm-inline"> sin i > sin C \;{1}/{µ}\;\; \;\text " or "\; \;{1}/{√{2}} > \;{1}/{µ} ⇒ µ > √{2} " class="fm-inline"> ⇒ sin 45 ∘ > 1 µ or 1 √ 2 > 1 µ ⇒ µ > √ 2 As refractive index for red colour is 1.39 which is less than √ 2 , so red will be transmitted through face A C while green and blue will be reflected." >
At face AB,i=0. So, r=0, i.e., light will be incident on face AC at an angle of incidence 45∘. The face AC will not transmit the light for which i>C. i.e. sini>sinC ⇒sin45∘>
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⇒µ>√2 As refractive index for red colour is 1.39 which is less than √2, so red will be transmitted through face AC while green and blue will be reflected.
