0/1 points 1 Previous Answers SercP11 23.PO0B To fit a contact lens to a patient
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0/1 points 1 Previous Answers SercP11 23.PO0B To fit a contact lens to a patient's eye, a keratometer can be used to measure the curvature of the cernes-the frant suface of the aye.Tha mt ld j that allows a comparison of the image formed by the cormea with a second cal brated image prejected into the held of vew Dy e prian e of n at a known distance p from the conea, which then reflects some ight from the obyet, forming an image o n inage is measred by sng a sma e cornea when p-25.0 cm and M-0.0160Explanation / Answer
1)
distance of the the object from cornea, p = 25 cm
magnification, M = 0.0160
from lens law
1/f = 1/p + 1/q
R/2 = 1/p + 1/q
magnification of the mirror is
M = -q/p
q = -Mp
q = - 0.0160 x 25 cm
q = -0.4
negative sign indicates that the image is backside of the surface of the cornea.
R/2 = 1/p + 1/q
R = 2pq / p + q
R = (2 x 25 x -0.4) / (25 - 0.4)
R = -0.81 cm
surface of the cornea is convex
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