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प्रश्न
Name the physical quantity whose unit is dioptre.
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उत्तर
The power of a lens is a physical quantity with dioptre as it's unit.
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संबंधित प्रश्न
What does sign of power (+ve or –ve) indicate?
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?
Two lenses A and B have focal lengths of +20 cm and, −10 cm, respectively.
(a) What is the nature of lens A and lens B?
(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?
A combination of lenses for a camera contains two converging lenses of focal lengths 20 cm and 40 cm and a diverging lens of focal length 50 cm. Find the power and focal length of the combination.A optical instrument in which the above arrangement of convex lens is used is a convex lens used to burn paper by focusing sunlight.
How is the power of a lens related to its focal length?
How does the power of a lens change if its focal length is doubled?
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Consider the situation described in the previous problem. Where should a point source be placed on the principal axis so that the two images form at the same place?
Focal length : metre : : power of lens : _______
If focal length of a convex lens is 20 cm at what is the power of the lens?
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Assertion and reasoning type
- Assertion: Myopia is due to the increase in the converging power of eye lens.
- Reason: Myopia can be corrected with the help of concave lens.
When monochromatic red light is used instead of blue light in a convex lens, its focal length will ______.
The focal length of a double convex lens is equal to the radius of curvature of either surface. What is the refractive index of its material?
