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NEET 2016 (Phase 1) · Prism, Dispersion & Scattering

Prism, Dispersion & Scattering question from NEET 2016 (Phase 1)

Q78NEET 2016 · PHASE 1Easy

Prism, Dispersion & Scattering

The angle of incidence for a ray of light at a refracting surface of a prism is 45°. The angle of prism is 60°. If the ray suffers minimum deviation through the prism, the angle of minimum deviation and refractive index of the material of the prism respectively, are

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Answer: (d)

  1. At minimum deviation δm=2i−A=2(45∘)−60∘=30∘\delta_m = 2i - A = 2(45^\circ) - 60^\circ = 30^\circ.
  2. Also r=A/2=30∘r = A/2 = 30^\circ.
  3. μ=sin⁡45∘sin⁡30∘=1/21/2=2\mu = \dfrac{\sin 45^\circ}{\sin 30^\circ} = \dfrac{1/\sqrt{2}}{1/2} = \sqrt{2}
  4. So the answer is (d) 30∘; 230^\circ;\ \sqrt{2}.
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