Question

The uncorrected eye. For the following questions, assume that the distance between the eye lens and...

The uncorrected eye. For the following questions, assume that the distance between the eye lens and the retina is 1.70 cm. In other words, since the image is always formed on the retina, the distance between the lens and the image is always 1.70 cm. Also note that, as is seen in the ray diagram, since the eye lens is converging and the image is on the opposite side of the lens compared to the object, the image is always real.

a. What is the focal length of the eye when an object is 25.0 cm away from the eye lens? \

b. What is the focal length of the eye when an object is very far away from the eye lens (object at infinity)?

c. One nearsighted patient has a far point of 400 cm. What is the focal length of her eye when an object is at her far point? How does this focal length compare to the focal length in part b?

d. One farsighted patient has a near point of 40.0 cm. What is the focal length of his eye when an object is at his near point? How does this focal length compare to the focal length in part a?

e. The nearsighted patient in part c tries to view an object that is very far away (object at infinity). Use the focal length calculated in part c to determine the location of the image. How does this compare to the distance from the eye lens to the retina? What kind of image is seen on the retina?

f. The farsighted patient in part d tries to view an object 25 cm away from his eye, which a person with normal vision can see clearly. Use the focal length calculated in part d to determine the location of the image. How does this compare to the distance from the eye lens to the retina? What kind of image is seen on the retina?

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