Answer to Question #282072 in Optics for Megh

Question

In case of large telescope objectives, the central position of the objective is covered with a stop so as to____

Answer 1

Magnification is given by

$=\large\frac{f_o}{f_e}$

So the magnification is directly proportional to the focal length of the objective lens and inversely proportional to the focal length of the eye piece. Hence it ensures large magnification of the distant object.