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Question
Kavita from 10th is using spectacles. The power of the lenses in her spectacles is –2.5 dioptre. Answer the following questions:
1) Which lenses are used in her spectacles?
2) State the defect of vision Kavita is suffering from.
3) Find the focal length of the lenses used in her spectacles
Solution
1) Concave lens
2) Myopia or nearsightedness
3) `f = 1/D = 1/2.5 = 0.4 m`
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