# Problem: Routinely, doctors test a patient's visual acuity, or ability to resolve small images properly, which typically involves reading progressively smaller letters until the patient can't make out the letters anymore. Someone with 20/20 vision can resolve an image of 1 arc minute (about 0.017o) of angular diameter from 20ft away. If the visual acuity test were set up to be 10ft away from the patient, at eye level, what is the smallest letter someone with 20/20 vision should be able to make out? Consider the wavelength of light to be 550 nm and the human pupil to be 12 mm in diameter.

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Routinely, doctors test a patient's visual acuity, or ability to resolve small images properly, which typically involves reading progressively smaller letters until the patient can't make out the letters anymore. Someone with 20/20 vision can resolve an image of 1 arc minute (about 0.017o) of angular diameter from 20ft away. If the visual acuity test were set up to be 10ft away from the patient, at eye level, what is the smallest letter someone with 20/20 vision should be able to make out? Consider the wavelength of light to be 550 nm and the human pupil to be 12 mm in diameter.