What is the focal length of a magnifying glass if a 1-mm object appears to be 10 mm?
A)1.4 cm
B)2.5 cm
C)3.1 cm
D)4.6 cm
E)5.2 cm

Question

Quizplus · Accepted Answer

The magnification (M) of a magnifying glass is given by the formula M = Image size / Object size. Here, M = 10 mm / 1 mm = 10. The magnification is also given by M = 25 / f, where f is the focal length in cm and 25 cm is the near point of the human eye. Solving 10 = 25 / f gives f = 2.5 cm.

What Is the Focal Length of a Magnifying Glass If