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Question
Magnification of a convex lens is ______.
Options
Positive
negative
either positive or negative
zero
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Solution
Magnification of a convex lens is either positive or negative.
Explanation:
A convex lens can form real or virtual images depending on the position of the object. If the image is real and inverted, the magnification is negative. If the image is virtual and erect, the magnification is positive. Therefore, magnification of a convex lens is either positive or negative.
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A student is using a convex lens of focal length 10 cm to study the image formation by a convex lens for the various positions of the object. In one of his observations, he may observe that when the object is placed at a distance of 20 cm from the lens, its image is formed at (select the correct option)
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