The focal length of the eye-piece of an astronomical telescope is f1, while the focal length of the object is f2. Fro normal adjustment, the angular magnification is given by
-
A.
(frac{f_2}{f_1}) -
B.
1 – (frac{f_2}{f_1}) -
C.
(frac{f_2}{f_1}) – 1 -
D.
(frac{f_1}{f_2})