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प्रश्न
A lens has a focal length of, −10 cm. What is the power of the lens and what is its nature?
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उत्तर
Power of a lens is given by:
Power (P) `=1/f``
`f=-10` cm
∴` p=1/(10xx10^2)=-10 D`
Negative sign indicates it is a diverging lens.
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