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प्रश्न
What is the nature of a lens having a power of + 0.5 D?
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उत्तर
Positive sign indicates it is a converging lens. Therefore, the lens is convex.
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संबंधित प्रश्न
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B: virtual image is always erect
Out of these two statements:
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(b) focal length of spectacle lens?
Fill in the following blank with suitable word:
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(b) What is the focal length of this combination?
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(b) state the nature of lens Y.
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(3) no image as the screen has been removed
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