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Question
Surabhi from std. X uses spectacle. The power of the lenses in her spectacle is 0.5 D.
Answer the following questions from the given information:
- Identify the type of lenses used in her spectacle.
- Identify the defect of vision Surabhi is suffering from.
- Find the focal length of the lenses used in her spectacle.
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Solution
1) The power is positive hence the convex lens
2) Hypermetropia
3) `"P" =1/"F"`
`"f" = 1/"P" = 1/0.5 = 2 "m"`
= 200 cm
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