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A. 65-year old emmetrope wearing +2.50D readers has a near point of accommodation of 25cm.what is his near point of accommodation without glasses? B. The patient above wishes to have glasses for reading material at 50cm. what should the appropriate power of the reading spectacles be?

Respuesta :

pstnonsonjoku

If he does not use the lenses, his near point will be  66.7 cm. For him to read a material at 50 cm, he  has to use  a lens of 2.0D.

What is the near point?

The near point is the nearest area which a person can see or have distinct vision. The focal length of the lens is f = 100/2.5 = 40cm

Then;

1/40 = -1/v + 1/25

1/v = 1/25 - 1/40

v = 66.7 cm

Also, for the purpose of reading at 50 cm

1/f = -1/50 + 1/25

1/f = 1/25 - 1/50

f = 50cm

The power of this lens is;

100/50 cm = 2 D

Learn more about lens: brainly.com/question/1503351

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