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प्रश्न
Explain what is meant by a virtual, magnified image.
उत्तर
A virtual image is an image formed by a lens/mirror that cannot be taken on a screen. A magnified image implies that the size of the image formed is larger than the size of the object.
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संबंधित प्रश्न
An object of height 4 cm is placed at a distance of 20 cm from a concave lens of focal length 10 cm. Use lens formula to determine the position of the image formed.
When an object is placed at a distance of 50 cm from a concave spherical mirror, the magnification produced is, `-1/2`. Where should the object be placed to get a magnification of, `-1/5`?
A concave mirror produces magnification of +4. The object is placed:
(a) at the focus
(b) between focus and centre of curvature
(c) between focus and pole
(d) between the centre of curvature
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Solve the following example.
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At which position will you keep an object in front of convex lens to get a real image smaller than the object? Draw a figure.
The lens of the eye is flattened when looking at nearby objects.
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- What is the magnification obtained by using the glass?
- She keeps a book at a distance 10 cm from her eyes and tries to read. She is unable to read. What is the reason for this?
Write an expression for magnification for a lens, explaining the meaning of the symbols used.
