For the angle of minimum deviation of a prism to be equal to its refracting angle, the prism must be made of a material whose refractive index:
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For the angle of minimum deviation of a prism to be equal to its refracting angle, the prism must be made of a material whose refractive index:

G1 Physics · Accepted Answer

Step 1: At minimum deviation, μ = sin[(A + δₘ)/2]/sin(A/2). Step 2: If δₘ = A, then μ = sin A/sin(A/2) = 2cos(A/2). Step 3: For a nonzero prism angle with 0° < A < 90°, cos(A/2) lies between √2/2 and 1. Step 4: Therefore √2 < μ < 2. Final answer: (B) between √2 and 2.