QQuestion
(a) In a reading glass what is the position of the object with respect to the convex lens used?
(b) Why can we not use concave lens for the same purpose?
✓Answer
(a) In a reading glass, the object is placed between the optical center and the principal focus of the convex lens to produce a virtual and enlarged image of the object so that a magnified view of the object can be seen.
(b) A concave lens always forms a virtual, erect, but diminished (smaller) image of the object so it cannot magnify the object.
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