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प्रश्न
The lens mentioned in 6(b) above is of focal length 25cm. Calculate the power of the lens.
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उत्तर
Focal length of a convex lens is always positive.
Given: f = +25 cm
`therefore P=1/f`
`P=1/25`
`P=+0.04D`
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संबंधित 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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