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प्रश्न
Define the power of a lens.
उत्तर
The power of a lens (P) is the ability of the lens to converge or diverge an incident beam falling on it. It is expressed as the reciprocal of focal length (f).
The power of a lens (P) is given by
`P=1/f("in metre")`
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संबंधित प्रश्न
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