A refracting telescope has a magnification M.If the focal length of the objective lens is doubled and the eyepiece focal length is halved,what is the new magnification?
A)4M
B)2M
C)M/2
D)M/4
E)M

Question

Quizplus · Accepted Answer

The magnification of a refracting telescope is given by the ratio of the focal length of the objective lens to the focal length of the eyepiece. If the focal length of the objective is doubled and the eyepiece focal length is halved, the new magnification is 4 times the original magnification (since both changes double the magnification effect).

A Refracting Telescope Has a Magnification M