The figure shows a simple arrangement which works as an astronomical telescope. The arrangement consists of two convex lenses placed coaxially. The lens which faces a distant object is called the objective. It has a large aperture and a large focal length also. The second lens is closed to the observers eyes. It is called the eyepiece. It has a smaller aperture as compared to the objective. Its focal length is also small in comparison to objective.
The objective forms a real image of a distant object. This image acts as the object for the eyepiece. The eye-piece may form its image at a large distance `(oo)` or at least distance of distinct vision (D = 25 cm). The magnifying power of the telescope is the ratio `(-beta)/(alpha)`. Maximum angular magnification is produced when the final image is at the least distance of distinct vision.
The angular magnification produced by the telescope `m = (-beta)/(alpha)`, let focal length of objective lens is `f_(0)` and that of eye-piece lens `f_(e)`. The angular magnification produced, when image formed by the eye-piece is at large distance away, is
A. `(-f_(0))/(f_(e))`
B. `-(1+(f_(0))/(f_(e)))`
C. `(-f_(e))/(f_(0))`
D. `-(1+(f_(e))/(f_(0)))`
