What type of lens from the following would you have in your magnifying lens to read a page in small print ?


A convex lens of focal length 80 cm


A concave lens of focal length 80 cm


A concave lens of focal length 4 cm


A convex lens of focal length of 4 cm

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Correct option is D)

A always produces virtual, erect and diminished images and the decrease in the size of the image depends on the position of the object. 
Concave lens will shrink the size of the already small letters. Hence, it is undesirable.

A produces real and virtual, erect and inverted, diminished, same sized and magnified image of the object, depending upon the position of the object on the principal axis.
When the object is placed at a distance less than the focal length of convex lens, an enlarged and erect image of the object is formed, which will make it easier to read small letters.

Hence, the correct answer is OPTION D. 

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