The graph below shows the variation of image distance (v) with the object distance (u) when an object is kept in front of a lens.
(a) Identify the type of lens used.
(b) What would be the magnification (more than 1 / less than 1 / equal to 1) if the object is placed between F and 2F of the above lens?
(a) The lens used is a convex lens.
(b) If the object is placed between F and 2F, the magnification will be more than 1.
Explanation:
(a) The graph shows that for an object placed in front of the lens, a real image is formed on the other side and the image distance changes according to the position of the object. This behaviour is shown by a convex lens.
(b) For a convex lens, when the object is placed between F and 2F, the image is formed beyond 2F. The image is real, inverted and magnified. Therefore, the magnification is more than 1.
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