A near-sighted person has a far point of 80 cm. A) What kind of corrective lens...

Question

Question

A near-sighted person has a far point of 80 cm.

A) What kind of corrective lens the person will need if the lens is to be placed 1.5 cm from the eye? The answer is not 78.5, 80 or -1.27

B) What would be the power of the contact lens needed? Assume distance to contact lens from the eye to be zero.

Answer 1

Answer #1

A)

Concave lens

B)

Focal length, f = 1/(1/infinity + 1/-80) = - 80 cm

Power, P = 1/-80 = - 1.25 D

Comment in case any doubt please rate my answer...

Answer 2

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