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Question
Magnifying power of a simple microscope is inversely proportional to the focal length of the lens. What then stops us from using a convex lens of smaller and smaller focal length and achieving greater and greater magnifying power?
Solution
Firstly, the process of making lenses with very short focal lengths (thick lenses) is not easy; secondly, as the focal length decreases, the defect of aberration in the lenses starts increasing. Due to this, the images formed by them become unclear. In reality, a single convex lens cannot achieve a magnification of more than 3, but a lens without an aberration defect can achieve a much higher magnification (about 10).
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