mpleted mpleted mpleted 3000 PM 2413 Begin Date 20000 AM Due

mpleted mpleted mpleted 30:00 PM 24.1-3 Begin Date 2:00:00 AM Due Date 6/2016 8:00:00 AM End Date: 5/132016 (13%) Problem 7: A ncar-sighted person has a far point of 80 cm. u sos Part (al what kind of corrective lens the person will need if the lens is to be placed 15cm from the TD N 50 Part (b) What would be the power of the contact lens needed? Assume distance to contact lens from the eye to be zero. Power I Grade Summary Deductions Potential 92% sino coso Ltano 7 8 9 Submissions asino acos Attempts remaining: 4 5 6 4% per attempt) atano acotano sinh0 2 3 detailed view cosh0 tanho cotanho 4% ODegrees Radians l give up! Hints: for a 0% deduction, Hints remaining Feedback: deduction per feedback. Alleennerec 2016 Expert TA.uc

Solution

a)

For a near-sighted person, the image is formed before the retina.

This is due to the fact that the curvature of the eyelens is too high so that it forms the image before the retina.

So, to correct this a diverging lens needs to be given so as to correct the large curvature of the eyelens <----answer

b)

Using the relation:

1/v + 1/u = 1/f

For objects far off, u = infinity

v = at the far point = -80 cm = -0.8m

So, 1/f = 1/-0.8 = -1.25

So, Power = 1/f = -1.25 D <--------answer