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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
Calculate the focal length of a corrective lens having power +2D.
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(b) state the nature of lens Y.
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- Identify the type of lens.
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In what unit is the power of a lens expressed?
