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प्रश्न
A person cannot see distant objects clearly. His vision can be corrected by using the spectacles containing:
(a) concave lenses
(b) plane lenses
(c) contact lenses
(d) convex lenses
उत्तर
concave lenses
Concave lenses are used to correct the defect of vision and enable the person to see distant objects clearly.
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संबंधित प्रश्न
If the numerical value of the power of this lens is 10 D, what is its focal length in the Cartesian system ?
Define the principal focus of a concave lens.
Which type of lenses are:
thinner in the middle than at the edges?
Give the position, size and nature of image of formed by a concave lens when the object is placed:
at infinity.
Construct ray diagrams to illustrate the formation of a virtual image using a diverging lens.
An object 60 cm from a lens gives a virtual image at a distance of 20 cm in front of the lens. What is the focal length of the lens? Is the lens converging or diverging? Give reasons for your answer.
The power of a concave lens is 10 D and that of a convex lens is 6 D. When these two lenses are placed in contact with each other, the power of their combination will be :
(a) +16 D
(b) +4 D
(c) −16 D
(d) −4 D
An object is placed on the axis of a lens. An image is formed by refraction in the lens. For all positions of the object on the axis of the lens, the positions of the image are always always between the lens and the object.State three characteristics of the image.
Convex lens : converging : : concave lens : _______
Distinguish between:
Concave Lens and Convex Lens
