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Human Eye and Colourful World — Science STD 10 — Question

CBSE BoardEnglish MediumSTD 10ScienceHuman Eye and Colourful World5 Marks
Question
Draw a diagram to show why distant objects cannot be seen distinctly by a myopic eye. List two reasons due to which this defect of vision may be caused. A person with a myopic eye
cannot see objects clearly beyond a distance of 2 m. Name the type of corrective lens that would be needed to correct the defect of vision and draw a ray diagram to show how the defect
gets corrected.
✓

Answer

In order to see objects by the eye the image of the object should form on the retina, exactly on the retina. When a person is suffering from Myopia or near sightedness, the near point
of distinct vision gets Increases and an object placed at a distance less than this new near point has its image formed in front of retina.

If a person can’t see the object clearly beyond 2m then he should use concave or diverging lens in order to correct his defect.

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