- #1
Badger
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Homework Statement
Joe is hiking through the woods when he decides to stop and take in the view. He is particularly interested in three objects: a squirrel sitting on a rock next to him, a tree a few meters away, and a distant mountain. As Joe is taking in the view, he thinks back to what he learned in his physics class about how the human eye works.
Joe first focuses his attention (and his eyes) on the tree. The focal length of the cornea-lens system in his eye must be __________ the distance between the front and back of his eye.
A - Greater Than
B - Less Than
C - Equal To
Homework Equations
None
The Attempt at a Solution
I don't know where to begin. I believe focal length on one side of a lens is the same as the focal length on the other side. But this problem talks about this cornea-lens system, a "compound lens system," which throws me off.
But here's my flow of logic, please feel free to comment.
-Our eyes are converging lenses
-Our eyes can change the focal length in order for us to focus on objects at different distances.
-The object is a real inverted image after it passes through our eye
-The image must focus on our fovea in order for it not to be a "sharp image"
-The fovea is at the back of the eye.
So if the fovea is at the back of our eye, which is where the image needs to be focused, that means the focal length is B) equal to that distance?