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प्रश्न
When an object is placed 10 cm in front of lens A, the image is real, inverted, magnified and formed at a great distance. When the same object is placed 10 cm in front of lens B, the image formed is real, inverted and same size as the object.
What is the focal length of lens A?
उत्तर
The focal length of lens A is 10 cm as only a converging lens forms a real, inverted, magnified image at great distance when object is placed at the focus of the lens.
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संबंधित प्रश्न
What type of image is always made by a concave lens?
Take down this figure into your answer book and complete the path of the ray.
Give the position, size and nature of image of formed by a concave lens when the object is placed:
at infinity.
When an object is kept at any distance in front of a concave lens, the image formed is always:
(a) virtual, erect and magnified
(b) virtual, inverted and diminished.
(c) virtual, erect and diminished
(d) virtual, erect and same size as object
(a) Find the position and size of the virtual image formed when an object 2 cm tall is placed 20 cm from:
(i) a diverging lens of focal length 40 cm.
(ii) a converging lens of focal length 40 cm.
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What kind of lens is used to correct
short-sightedness
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 Draw a ray diagram to show it.
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Copy the following figure and complete it to show the formation of the image of the object AB. Name the lens used in the figure.
