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3 years ago

6

The near point of an eye is 56.0 cm. A corrective lens is to be used to allow this eye to focus clearly on objects at the distan

ce of the healthy near point. What should be the focal length of this lens

1 answer:

irakobra [83]3 years ago

4 0

Answer:

Explanation:

Near point = 56 cm .

near point of healthy person = 25 cm

person suffers from long sightedness

convex lens will be required .

object distance u = 25 cm

image distance v = 56 cm

both will be negative as both are in front of the lens.

lens formula

I/v - 1 / u = 1/f

- 1/56 +1/25 = 1/f

- .01785 + .04 = 1/f

1/f = .02215

f = 45.15 cm .

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Complete Question

The diagram for this question is shown on the first uploaded image

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Explanation:

From the question we are told that

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This can be mathematically represented as

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From above

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Substitute this into above equation

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3 years ago