TABLE 25 .

A 30-year-old optometry patient focuses on a 6.50 cm -tall photograph at his near point. (See the table.) We can model his eye as a sphere 2.50 cm in diameter, with a thin lens at the front and the retina at the rear.(Figure 1)

A. What is the effective focal length of his eye when he focuses on the photo?

B. What is the power of his eye in diopters when he focuses on the photo?

c. How tall is the image of the photo on his retina?

D. If he views the photograph from a distance of 2.50 m , how tall is its image on his retina?