Science
The below image shows a corrective measure for a particular defect of vision.
(a) Identify the defect of vision and state what kind of lens is used to correct this deficiency.
(b) Draw and label a ray diagram that shows the defect of vision in the above case before correction.
Answer
(a) The defect of vision shown is hypermetropia (long-sightedness).
Explanation : In this defect, the eye cannot focus clearly on near objects because the image of a nearby object is formed behind the retina so to correct this, a convex (converging) lens is used in front of the eye. The convex lens first converges the diverging rays from the near object so that, after refraction through the eye lens, the image forms exactly on the retina
(b) The labelled ray diagram showing hypermetropia defect is given below :
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