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JEE Main · 2021 · 18 Mar 2021 · Shift 1 · Geometrical Optics

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Your friend is having eye sight problem. She is not able to see clearly a distant uniform window mesh and it appears to her non-uniform and distorted. The doctor diagnosed the problems as:
  1. (A)Myopia with Astigmatism✓ Correct
  2. (B)Myopia and hypermetropia
  3. (C)Astigmatism
  4. (D)Presbyopia with Astigmatism

Answer: (A)

Solution

Failure to see a distant object sharply means parallel rays are brought to a focus in front of the retina, which is myopia. A uniform mesh looking non-uniform and distorted means the horizontal and the vertical lines of the mesh are not focused equally sharply; this happens when the cornea or the lens has different curvatures, and hence different focal lengths, in different meridians, and that defect is astigmatism. The diagnosis is myopia with astigmatism.

JEE Main · 2021 · 18 Mar 2021 · Shift 1 · Single correct option

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