Question

A horizontal ray is incident on a right-angled prism with prism angle of 4°. If the refractive index of material of the prism is 1.5, angle of emergence is ________ . Use the given figure.(A) 4°
(B) 6°(D) 10°
(D) 0°

Answer 1

we know the relation, $\delta=i+e-A$
also $\delta=(\mu-1)A$

where $\delta$ is the deviation angle , i is the incident angle , e is the emergent angle and A is angle of prism.

given, $\mu$ = 1.5 ,A = 4° , i = 0°
now, (1.5 - 1) × 4° = 0° + e - 4°
e = 2° + 4° = 6°

hence, angle of emergence = 6°
therefore option (B) is correct.