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If the radius of curvature of the cornea is 0.75 cm when the eye is focusing on an object 36.0 cm from the cornea vertex and the indexes of refraction are as described before, what is the distance from the cornea vertex to the retina

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Answer:

The distance from the cornea vertex to the retina is 2.36 cm

Step-by-step explanation:

The question is incomplete.

The complete question is as follows;

A Nearsighted Eye. A certain very nearsighted person cannot focus on anything farther than 36.0 cm from the eye. Consider the simplified model of the eye. In a simplified model of the human eye, the aqueous and vitreous humors and the lens all have a refractive index of 1.40, and all the refraction occurs at the cornea, whose vertex is 2.60 cm from the retina.

If the radius of curvature of the cornea is 0.65 cm when the eye is focusing on an object 36.0 cm from the cornea vertex and the indexes of refraction are as described before, what is the distance from the cornea vertex to the retina?

Solution.

We use image-object reaction to calculate the distance from the cornea vertex to the retina.

Mathematically;

n1/s + n2/s’ = n2-n1/R

From the question, we identify the following;

n1 ; Refractive index of air = 1

n2 ; Refractive index of lens = 1.4

S ; Object Distance = 36 cm

S’ = ?

R ; Radius of curvature of the cornea = 0.65

Substituting these values into the equation above;

1/36 + 1.4/S’ = (1.4-1)/0.65

{S’+ 36(1.4)}/36S’ = 0.4/0.65

{S’ + 50.4}/36S’ = 0.62

S’ + 50.4 = 22.32S’

50.4 = 22.32S’ -S’

21.32S’ = 50.4

S’ = 50.4/21.32

S’ = 2.36 cm

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