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प्रश्न
State whether the following statement is true or false:
Short-sightedness can be cured by using a concave lens.
उत्तर
True.
Short-sightedness can be corrected by using concave lenses.
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संबंधित प्रश्न
A small bulb is placed at the focal point of a converging lens. When the bulb is switched on, the lens produces:
(a) a convergent beam of light
(b) a divergent beam of light
(c) a parallel beam of light
(d) a patch of coloured light
What type of image is always made by a concave lens?
Which type of lens is :
a converging lens, and which is
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?
If the image formed by a lens is diminished in size and erect, for all positions of the object, what type of lens is it?
A student obtained clear image of window grills on the screen. But the teacher told him to get the image of a tree far away, instead of window. To get a clear image, the lens must be ............................
An object is placed at a distance 24 cm in front of a convex lens of focal length 8 cm.
(i) What is the nature of the image so formed?
(ii) Calculate the distance of the image from the lens.
(iii) Calculate the magnification of the image.
A concave lens has a focal length 30 cm. Find the position and magnification (m) of the image for an object placed in front of it at distance 30 cm. State whether the image is real or virtual?
When an object is kept within the focus of a concave mirror, an enlarged image is formed behind the mirror. This image is :
Identify the device used as a spherical mirror or lens in following case, when the image formed is virtual and erect in case.
Object is placed between infinity and device, image formed is diminished and between focus and optical centre on the same side as that of the object.
