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प्रश्न
What is meant by a power of a lens? Define its SI unit.
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उत्तर १
The power of a lens is defined as the reciprocal of its focal length. It is represented by the letter P. The power P of a lens of focal length f is given as
P = 1/f
The SI unit of power is dioptre (D).
उत्तर २
Power of lens: Power of lens is defined as its ability to converge or diverge the rays of light falling on it. SI unit of power is Dioptre.
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संबंधित प्रश्न
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(b) What is the magnification in this case?
(c) Is the magnification equal to the magnifying power in this case? Explain.
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(i) Name the Lens LL’.
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(iii) State three characteristics of the image.
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