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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
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