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प्रश्न
The magnification by a lens is -3. Name the lens and state how are u and v related?
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उत्तर
The negative value of magnification suggests that image is real and inverted. The magnitude of magnification is greater than 1 which means image is enlarged. Therefore the lens should be convex lens.
Relation between u and v is given by
m = `"v"/"u"`
`-3 = "v"/-"u"`
v = 3 u
This shows that image distance is 3 times that of object distance.
संबंधित प्रश्न
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A convex lens produces on a screen an image twice the size of the object. If the position of image and object be interchanged, what will be the magnification then?
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