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NEET 2020 (Phase 1) · Refraction, Glass Slab & Apparent Depth

Refraction, Glass Slab & Apparent Depth question from NEET 2020 (Phase 1)

Q63NEET 2020 · PHASE 1Easy

Refraction, Glass Slab & Apparent Depth

The Brewster's angle ib for an interface should be:

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Answer: (b)

  1. Brewster's law: tan⁡ib=n2n1\tan i_b = \dfrac{n_2}{n_1}.
  2. For light going from rarer to denser medium (the usual case, e.g. air to glass), n2>n1n_2 > n_1, so tan⁡ib>1\tan i_b > 1.
  3. tan⁡ib>1⇒45∘<ib<90∘\tan i_b > 1 \Rightarrow 45^\circ < i_b < 90^\circ (ib=90∘i_b = 90^\circ would need n2→∞n_2 \to \infty).
  4. So the answer is (b).
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