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प्रश्न
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
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उत्तर
1) Concave lens
2) Myopia or nearsightedness
3) `f = 1/D = 1/2.5 = 0.4 m`
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