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प्रश्न
How is the power of a lens related to its focal length?
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उत्तर
The power of a lens is related to the focal length as:
Power (P)=`I/f'`
where, f is measured in metres and P in dioptres.
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संबंधित प्रश्न
Define 1 dioptre of power of a lens.
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(b) a piece of white paper
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Which one of the following materials cannot be used to make a lens?
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(b) focal length of this combination of lenses?
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(b) state the nature of lens Y.
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