For a prism, the minimum deviation δ_m is equal to the prism angle A. If the re \fractive \fractive \fractive index is √3, find the minimum deviation.
Physics · Geometrical optics · prism and thin prism
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Question

For a prism, the minimum deviation δ_m is equal to the prism angle A. If the re \fractive \fractive \fractive index is √3, find the minimum deviation.

G1 Physics · Accepted Answer

At minimum deviation, μ=sin[(A+δ_m)/2]/sin(A/2). Since δ_m=A, μ=sinA/sin(A/2)=2cos(A/2). Thus √3=2cos(A/2), so A/2=30°, A=60°. Hence δ_m=60°.