A farsighted man with eyeglasses problem

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A farsighted man with a refractive power of 2.20 diopters seeks a contact lens prescription that allows him to read at a minimum distance of 0.28 m. The discussion involves calculating the focal distance and the impact of the glasses being positioned 0.03 m from the eyes. Participants express confusion about how to adjust the calculations for contact lenses, which sit directly on the eye. The thread highlights the need for clarity on the relationship between glasses and contact lens prescriptions. Overall, the focus remains on determining the appropriate contact lens prescription based on the given parameters.
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Homework Statement


A farsighted man uses eyeglasses with a refractive power of 2.20 diopters. Wearing the glasses 0.03 m from his eyes, he is able to read books held no closer than 0.28 m from his eyes. He would like a prescription for contact lenses to serve the same purpose. What is the correct contact lens prescription, in diopters?


Homework Equations


1/do + 1/di = 1/f


The Attempt at a Solution


well starting off i figured if the power is +2.20 dipoeters then the fd is going to be -1/2.20
not sure but since with the glasses it would be 1/fd-.03? and then with the contacts what would happen since there no distance? I am just really confused now lol
 
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Find out at what distance d from the eye the image forms with the ordinary eyeglasses when the book is held at 0.28 m from the eye. What should be the focal distance when the lens is on the eye and the distance of the image is equal to d in the same situation?

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