Ophthalmic OpticsQuestion 1 of 100
What is the focal length of a +2.00 D lens?
a.10 cm
b.25 cm
c.50 cm
d.200 cm
Explanation
Focal length in meters equals 1 divided by the lens power in diopters. 1 / 2.00 = 0.50 m, or 50 cm. A stronger plus lens would have a shorter focal length.
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