Eyes: What is the uncorrected near point of a person who has a near point that is 25 cm from his eyes when he is wearing 3.33-diopter contact lenses?

Question

Quizplus · Accepted Answer

The power of the contact lenses is 3.33 diopters, which means they have a focal length of 1/3.33 meters (approximately 0.30 m). The near point with the lenses is 25 cm (0.25 m). Using the lens formula (1/f = 1/v - 1/u), where v is the image distance (near point with lenses) and u is the object distance (uncorrected near point), we can solve for u. This gives an uncorrected near point of approximately 1.5 m.

Eyes: What Is the Uncorrected near Point of a Person