Find the value of the angle of emergence from the prism. Refractive index of the glass is √(3).

Find the value of the angle of emergence from the prism. Refractive index of the glass is \(\sqrt{3}\).

right-angled prism with 60 degree angle and ray incident normally on hypotenuse

1. \(60^\circ\)

2. \(30^\circ\)

3. \(45^\circ\)

4. \(90^\circ\)

Doubtly Asked 30 Oct 2026 NEET UG 2021 Practice test neet Save WhatsApp Report

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Answer: 1. \(60^\circ\)

Key idea: a ray hitting a face along its normal goes straight in; then apply Snell's law at the next face.

The ray enters the hypotenuse along the normal, so it is not deviated.
The hypotenuse makes 60° with the base, so the ray makes 30° with the base and strikes the vertical face with angle of incidence \(i=30^\circ\). Since \(\sin C = 1/\sqrt3 \approx 0.58\), \(C\approx 35^\circ\) and \(30^\circ
\(\sqrt3\sin 30^\circ = \sin r \Rightarrow \sin r=\dfrac{\sqrt3}{2}\Rightarrow r=60^\circ\).

Angle of emergence = 60°. Option 1.

Doubtly AI · 30 Oct 2026 AI-generated · not yet verified Report

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