You have a choice between two lenses of focal lengths f_a and f_b = 2 f_a to use as objective lens in building a compound microscope. If the magnification you obtain using lens A is M_a, what will be the magnification when using lens B? A) M_b = 2 M_a B) M_b = 4 M_a C) M_b = 8 M_a D) M_b = M_a /4 E) M_b = M_a /2

Question

Quizplus · Accepted Answer

Magnification of a compound microscope is given by the product of the magnification of the objective lens and the eyepiece lens. Since the objective lens in lens B has twice the focal length of lens A, it will have half the magnification. Therefore, the magnification when using lens B will be half of the magnification when using lens A, which can be represented as: M_b = M_a /2

You Have a Choice Between Two Lenses of Focal Lengths