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For a thin symmetric prism made of glass (refractive index 1.5), the ratio of incident angle and minimum deviation will be ______.

Asked in JEE Main 2nd April 1st Shift 2026 · Deviation and minimum deviation

Answer: (2) 3 : 2

Step-by-step solution

Thin prism: δₘ = (μ - 1)A = A/2.

At minimum deviation i = (A + δₘ)/2 = (3A)/4 (same as i = μ r = 1.5 · A/2).

i/(δₘ) = (3A/4)/(A/2) = 3/2

Why the other options are wrong

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