A plane polarized blue light ray is incident on a prism such that there is no reflection from the surface of the prism. The angle of deviation of the emergent ray is $δ = 60^{o}$ (see Figure- $1$ ). The angle of minimum deviation for red light from the same prism is $δ_{\min} = 30^{o}$ (see Figure- $2$ ). The refractive index of the prism material for blue light is $\sqrt{3}$ . Which of the following statement(s) is(are) correct?

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Aicharya · Accepted Answer

For no reflection: tan i = 3 &#8658; i = 60 &#176; Applying Snell's law at left interface, we get &#8658; 1 &#215; sin i = 3 &#215; sin r 1 &#8658; sin r 1 = 1 2 &#8658; r 1 = 30 o Now, for given values &#948; = i + e - A &#8658; 60 &#176; = 60 &#176; + e - A &#8658; e = A Then, A = r 1 + r 2 &#8658; r 2 = A - r 1 = 30 o For red light: Expression to find minimum deviation is given by, &#956; = sin A + &#948; m 2 sin A 2 = sin 60 &#176; + 30 &#176; 2 sin 60 &#176; 2 = 1 2 1 2 = 2

A plane polarized blue light ray is incident on a prism such that there is no reflection from the surface of…

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