A ray of light travels from glass (μ=1.5) to air. Critical angle is MCQ with Answer and Explanation

A ray of light travels from glass (μ=1.5) to air. Critical angle is
A. sin⁻¹(1/3)
B. sin⁻¹(1/1.5)
C. sin⁻¹(1.5)
D. sin⁻¹(2/3)
Answer: Option B
Solution (By JKSSB Mock Tests)
sin C = 1/μ = 2/3 ≈ 0.6667, C = sin⁻¹(2/3). So option A: sin⁻¹(2/3). Wait sin C = n2/n1 = 1/1.5 = 2/3. So C = sin⁻¹(2/3). Option A is sin⁻¹(2/3). I'll correct to A.

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