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A person can focus objects clearly only between 15 cm and 40 cm.

  • Thread starter greg_k92
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  • #1
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Homework Statement


A person can focus objects clearly only between 15 cm and 40 cm. What eyeglasses would you prescribe


Homework Equations


1/p+1/q=1/f
P=1/f


The Attempt at a Solution


I don't really know what to use for p, or f
 

Answers and Replies

  • #2
rude man
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Did they teach you about the eye?
q = distance from eye lens to retina
p = distance from object viewed to eye lens

Now think - you want the person to see things at p = infinity but you also want them to focus as close-in as possible, given their innate limitation (uncorrected, p = 15cm to p = 40 cm).
 

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