A person cannot see objects distinctly placed beyond 1.2 m. What type of corrective lens is required to restore normal vision?
Answer and explanation
Correct answer: A. Concave lens of power
- Step 1: The person suffers from myopia (nearsightedness) because the far point has shifted to .
- Step 2: To see distant objects at infinity (), the virtual image must form at the far point ().
- Step 3: Focal length: .
- Step 4: Power: (diverging concave lens).
Answer
Concave lens of power .
Why not the others: A convex lens converges light, worsening myopic image formation in front of retina; cylindrical lenses correct astigmatism; and uses the distance directly as power.
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