A ray of light passes from air to glass (refractive index 1.5). If angle of incidence is 30°, angle of refraction is (sin30=0.5) MCQ with Answer and Explanation

Question

A ray of light passes from air to glass (refractive index 1.5). If angle of incidence is 30°, angle of refraction is (sin30=0.5)

A. 45°

B. 60°

C. 30°

D. 19.47°

Answer: Option D

Solution (By JKSSB Mock Tests)

Snell's law: n₁ sin i = n₂ sin r. 1×0.5 = 1.5 sin r => sin r = 0.5/1.5 = 1/3 ≈ 0.3333 => r ≈ 19.47°. So A.

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