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प्रश्न
On reducing the focal length of a lens, its power ______.
विकल्प
Decreases
Increases
Does not change
First increases then decreases.
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उत्तर
On reducing the focal length of a lens, its power increases.
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संबंधित प्रश्न
Define the power of a lens.
Fill in the following blank with suitable words :
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