Physics quiz question: glasses for farsighted student later developing presbyopia

Physics 205B Quiz 2, spring semester 2016
Cuesta College, San Luis Obispo, CA

A Physics 205B student currently wears glasses to correct for farsightedness. If this Physics 205B student later develops presbyopia, __________ glasses will be prescribed.
(A) converging.
(B) diverging.
(C) bifocal.
(D) (Not enough information is given.)

Correct answer (highlight to unhide): (A)

The student is currently farsighted, and wears glasses to see nearby things. This means that the student's glasses are currently converging lenses, in oder to take an object at the nominal reading distance of 25.0 cm, and create an upright, virtual image at the more distant uncorrected near point for this student.

When the student later develops presbyopia, this is the loss of the ability to accommodate in order to focus on nearby objects, and thus the student will at best still wear the same prescription converging lens glasses, or may require a stronger prescription converging lens glasses.

Sections 30882, 30883
Exam code: quiz02f3MA
(A) : 17 students
(B) : 8 students
(C) : 16 students
(D) : 0 students

Success level: 41%
Discrimination index (Aubrecht & Aubrecht, 1983): 0.42