For a prism, A = 6 0 ∘ , refractive index n = 7/3 placed in air, the maximum possible angle of deviation, without suffering total internal reflection at the second surface, is δ max = n π ( radi

Question

For a prism, A = 6 0 ∘ , refractive index n = 7/3 ​ placed in air, the maximum possible angle of deviation, without suffering total internal reflection at the second surface, is δ max ​ = n π ​ ( radian ) find n = ?

TestHub · Accepted Answer

Applying Snell's law, we get: 1 × sin i m i n ​ = 3 7 ​ ​ sin ( A − C ) = 3 7 ​ ​ ( sin A cos C − cos A sin C ) = 3 7 ​ ​ ( sin 6 0 ∘ 1 − 7 3 ​ ​ − cos 6 0 ∘ 7 3 ​ ​ ) = 2 1 ​ Thus, i m i n ​ = 3 0 ∘ . The maximum deviation is δ m a x ​ = i m i n ​ + 9 0 ∘ − A = 3 0 ∘ + 9 0 ∘ − 6 0 ∘ = 6 0 ∘ .

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