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Physics · PYQ NEET UG 2016(1)
हिन्दीThe angle of incidence for a ray of light at a refracting surface of a prism is \( 45^\circ \). The angle of prism is \( 60^\circ \). If the ray suffers minimum deviation through the prism, the angle of minimum deviation and refractive index of the prism respectively, are
Correct answer · Option 2
\( 30^\circ; \sqrt{2} \)
Explanation
Given \( i = 45^\circ \), \( A = 60^\circ \). For minimum deviation, \( i = \frac{A + \delta_m}{2} \implies 45^\circ = \frac{60^\circ + \delta_m}{2} \implies \delta_m = 30^\circ \). Refractive index \( \mu = \frac{\sin((A+\delta_m)/2)}{\sin(A/2)} = \frac{\sin 45^\circ}{\sin 30^\circ} = \sqrt{2} \).
