Question

A person can see clearly only the objects situated in the range 50 cm to 300cm. He went to an Optometist who prescribed him a lens of certain power to increase the maximum distance of his vision to infinity , i.e., it corrected the near-sightedness. However, upon using the prescribed lens the person discovered that the near point of his vision has shifted from 50 cm to a distance ìdî. What is the value of d ?

Answer 1

Answer:

Explanation:

here in this case the man has to use concave lens to correct his defect in his eye.now the defective eye far point is at 300 cm so the focal length to the concave lens must be 300 cm and rays parallel to the axis after refraction by the concave lens will appear to be diverging from a point at 300 cm.now if he uses the concave lens then the image distance will be 50 cm and focal length will be 300 cm.