The optical prescription for a pair of spectacles is:
Right eye: 3.50D, Left eye: 4.00D
Right eye: 3.50D, Left eye: 4.00D
- Are these lenses thinner at the middle or at the edges?
- Which lens has a greater focal length?
- Which is the weaker eye?
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- These lenses are thinner at the middle because they are concave lens. Further, concave lens has negative power.
- Lens for right eye has greater focal length because power is inversely proportional to focal length.
- Left eye is weaker because it has a correction with a lens of lower focal length.
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