A magnifying glass has a focal length of 15 cm. If the near point of the eye is 25 cm from the eye the angular magnification of the glass is about:

Question

Quizplus · Accepted Answer

The angular magnification (M) of a magnifying glass is given by M = 1 + (D/f), where D is the near point of the eye (25 cm in this case) and f is the focal length of the magnifying glass (15 cm). Substituting the given values, M = 1 + (25/15) = 1 + 1.67 = 2.67. However, the question seems to ask for the magnification in a different context than the formula provided. The correct application for magnification in this context, considering the typical approximation for small angles, should be M = D/f, leading to M = 25/15 = 1.67. The discrepancy in the answer choices suggests a misunderstanding in the question's formulation or a typographical error in the options provided. Given the options, 1.7 (D) is the closest to the correct calculation based on the standard formula for optical magnification, despite the initial explanation suggesting a different approach.

A Magnifying Glass Has a Focal Length of 15 Cm