Which property of a telescope determines its light-gathering power?
A) the focal length of the objective
B) the focal length of the eyepiece
C) the diameter of the primary
D) the length of the telescope tube

Question

Quizplus · Accepted Answer

The light-gathering power of a telescope is determined by the diameter of the primary mirror or lens (the objective). A larger diameter allows the telescope to collect more light, making faint objects more visible.

Which Property of a Telescope Determines Its Light-Gathering Power