NEETPhysicsGeometrical OpticsMCQ+4 / −1
For a normal eye, the cornea of eye provides a converging power of 40 D and the least converging power of the eye lens behinf the cornea is 20 D. Using this information, the distance between the retina and the cornea-eye lens can be estimated to be
- A1.67 cm
- B1.5 cm
- C5 cm
- D2.5 cm
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Correct answer: A
Pcornea = + 40 D
Pe = + 20 D
Total power of combination = 40 + 20 = 60 D
Focal length of combination = cm = cm
For minimum converging state of eye lens,
u = - v = ? f =
From lens formula,
v = cm
Distance between retina and cornea-eye lens
= cm = 1.67 cm
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