A nearsighted person cannot see objects beyond 80 cm from his eyes. Which one of the following combinations represents the correct focal length and the refractive power of the contact lenses that
Will enable him to comfortably see the distant objects clearly?
A) $- 80 \mathrm {~cm} , - 1.3$ diopters
B) $- 1.3 \mathrm {~cm} , + 1.3$ diopters
C) $+ 80 \mathrm {~cm} , - 1.3$ diopters
D) $+ 80 \mathrm {~cm}$, $+ 1.3$ diopters
E) $- 80 \mathrm {~cm} , + 1.3$ diopters

Question

A nearsighted person cannot see objects beyond 80 cm from his eyes. Which one of the following combinations represents the correct focal length and the refractive power of the contact lenses that
Will enable him to comfortably see the distant objects clearly? 
A) $- 80 \mathrm {~cm} , - 1.3$ diopters
B) $- 1.3 \mathrm {~cm} , + 1.3$ diopters
C) $+ 80 \mathrm {~cm} , - 1.3$ diopters
D) $+ 80 \mathrm {~cm}$, $+ 1.3$ diopters
E) $- 80 \mathrm {~cm} , + 1.3$ diopters

Quizplus · Accepted Answer

A nearsighted person needs diverging lenses to correct their vision, which have a negative focal length. The refractive power (P) is calculated as $P = \frac{1}{f}$, where $f$ is the focal length in meters. For a focal length of $-80$ cm ($-0.8$ m), $P = \frac{1}{-0.8} = -1.25$ diopters, which rounds to $-1.3$ diopters, matching option A.

A Nearsighted Person Cannot See Objects Beyond 80 Cm from His