Which of the following lenses would you prefer

Question.
Which of the following lenses would you prefer to use while reading small letters found in a dictionary?

(a) A convex lens of focal length 50 cm

(b) A concave lens of focal length 50 cm

(c) A convex lens of focal length 5 cm

(d) A concave lens of focal length 5 cm

solution:
Option (c) is correct.

For reading small letters in a dictionary, a convex lens of small focal length is used as it is kept quite close to the page of the dictionary.

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