(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Suppose the lens in a human eye has far focal length equal to f0 = 40.1 mm, for distant objects to be in focus.

A. An object K is 1.69 m from the lens. How much should the focal length change to focus on the object K?

B.What is the magnification ( = image size divided by object size) for the object K?

2. Relevant equations

1/d_{i}+1/d_{o}=1/f

3. The attempt at a solution

A.1/1690+1/x=1/40.1

x=41.0746 mm

Thus, delta f = .9746 mm but that's wrong for some reason... but it's been a long week...

B.-f_{2}/f_{1}=M

Can someone help me out here?

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# Homework Help: Eye focusing

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