What is the magnification of a Newtonian telescope that has a primary mirror of diameter 0.25 m and focal length of 2 m when used with an eyepiece of focal length 25 mm and an optical diameter of 5 mm?
A) 50 times
B) 10 times
C) 80 times
D) 400 times

Question

Quizplus · Accepted Answer

The magnification of a telescope is given by the ratio of the focal length of the primary mirror (or lens) to the focal length of the eyepiece. Here, it is $ \frac{2000 \, \text{mm}}{25 \, \text{mm}} = 80 $ times.

What Is the Magnification of a Newtonian Telescope That Has