Q115
General ScienceBiology
Short-sight defect could be corrected by a
- a.convex lens
- b.concave lens
- c.converging lens
- d.None of the above
Answer: (B) concave lens
In short-sightedness (myopia) the eye can see near objects but distant objects are focused in front of the retina; it is corrected by a concave (diverging) lens. A convex lens is the same thing as a converging lens, so options (A) and (C) both describe the correction for long-sightedness (hypermetropia). Presbyopia of old age needs bifocal lenses and astigmatism needs cylindrical lenses.