Question

Find angle minimum deviation of an equilateral prism $(\mu =1.732)$. Also find angle of incidence for this deviation.

• A. ${60}^{\circ },{75}^{\circ }$
• B. ${60}^{\circ },{55}^{\circ }$
• C. ${60}^{\circ },{50}^{\circ }$
• D. ${60}^{\circ },{60}^{\circ }$

Answer 1

The correct option is D ${60}^{\circ },{60}^{\circ }$

$\mu =\frac{\sin \frac{A+D_m}{2}}{\sin \frac{A}{2}}$

$or\sqrt{3}\times \frac{1}{2}=\sin \frac{A+D_m}{2}\Rightarrow D_m{=60}^{\circ }$

$using2i=A+D_m,wegeti{=60}^{\circ }$