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प्रश्न
A diverging lens has a focal length of 0.10 m. The power of this lens will be:
विकल्प
+10.0D
+1.0D
−1.0D
−10.0D
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उत्तर
10.0D,
since power of lens=`1/"focal length"=1/-0.10=-10.0D`
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