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प्रश्न
What is the unit of power of a lens? Define the unit of power of a lens.
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उत्तर
The unit for the power of a lens is a dioptre (D). One dioptre is the power of a lens whose focal length is 1 metre.
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संबंधित प्रश्न
What is meant by a power of a lens? Define its SI unit.
What does sign of power (+ve or –ve) indicate?
How unit of power related to focal length of a lens?
Define 1 dioptre of power of a lens.
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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.
Which one of the following materials cannot be used to make a lens?
A lens has a focal length of, −10 cm. What is the power of the lens and what is its nature?
An object of height 4 cm is placed at a distance of 15 cm in front of a concave lens of power, −10 dioptres. Find the size of the image.
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(b) state the nature of lens Y.
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(b) What is the power of lens A and lens B?
(c) What is the power of combination if lenses A and B are held close together?
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(i) Name the Lens LL’.
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The power of a lens in dioptres is given by:
A concave lens is a diverging lens whose focal length and power are both:
A negative power of a lens indicates a:
The power of a lens of focal length \[f = 0.5\,m\] is:
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