A young woman with normal distant vision has a 13.0% ability to accommodate (that is, increase) the power of her eyes. What is the closest object she can see clearly? (Assume the lens-to-retina distance is 2.00 cm.)

0. Whatwas the previous far pointof a patientwho had laser vision correction that  

reduced the power of her eye by 7.00 D, producing normal distantvision for her?

Solution Since normal distantvision has apowerof50.0D (Example 26.2)and the laser vision

correction reduced the power of her eye by 7.00 D, she originally had apower of 57.0

D.We can determine her original far pointusing

0 143 m

0 0200 m

1 57 0 D 1 1 1

1 1

i

o

o i

. . . d

d P

d d

P ⎟ = ⎠

⎞ ⎜

⎝

⎛ = − ⎟

⎟

⎠

⎞

⎜

⎜

⎝

⎛ = + ⇒ = −

− −

Originally, withoutcorrective lenses, she could only see images 14.3 cm (or closer) to

hereye.

14. A young woman with normal distantvision has a 10.0% ability to accommodate (that  

is, increase) the power of her eyes. Whatis the closestobjectshe can see clearly?

Solution From Example 26.2, the normal power for distantvision is 50.0 D. For this woman

Explanation:

you have to draw the persons position over there

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