A ray of light suffers minimum deviation when incident on a prism having angle of the prism equal to $60^{\circ}$. The refractive index of the prism material is $\sqrt{2}$. The angle of incidence (in degrees) is__________
Answer (integer)
45
Solution
<p>To find the angle of incidence when a ray of light experiences minimum deviation in a prism, we use the formula for the refractive index $\mu$:</p>
<p>$ \mu = \frac{\sin \left(\frac{A + \delta_m}{2}\right)}{\sin \left(\frac{A}{2}\right)} $</p>
<p>Given:</p>
<p><p>The angle of the prism, $A = 60^{\circ}$</p></p>
<p><p>The refractive index of the prism material, $\mu = \sqrt{2}$</p></p>
<p><p>Minimum deviation, $\delta_m = 30^{\circ}$</p></p>
<p>At minimum deviation, the angle of incidence $i$ equals the angle of emergence $e$. Therefore, the relation between the angle of minimum deviation and the angle of the prism is represented as:</p>
<p>$ \delta_m = 2i - A $</p>
<p>Solving for $i$:</p>
<p>$ \delta_m = 2i - A \implies 30^{\circ} = 2i - 60^{\circ} \implies 2i = 90^{\circ} \implies i = 45^{\circ} $</p>
<p>Thus, the angle of incidence is $45^{\circ}$.</p>
About this question
Subject: Physics · Chapter: Optics · Topic: Refraction and Snell's Law
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