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प्रश्न
Calculate the focal length of a corrective lens having power +2D.
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उत्तर
Given: Focal length f = +2 D
Power ,p=1/f
∴f=1/p=1/2
∴f=0.5m
The power of the corrective lens is 0.5 m.
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संबंधित प्रश्न
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