In general, doubling the diameter of an optical telescope will
A) quadruple the light-gathering power and improve the angular resolution by a factor of 2.
B) quadruple the light-gathering power and improve the angular resolution by a factor of 4.
C) double the light-gathering power and improve the angular resolution by a factor of 2.
D) double the light-gathering power and improve the angular resolution by a factor of 4.

Question

Quizplus · Accepted Answer

Doubling the diameter of an optical telescope quadruples its light-gathering power because the area (and thus the light-gathering power) is proportional to the square of the diameter. It also improves the angular resolution by a factor of 2, as the resolution is inversely proportional to the diameter.

In General, Doubling the Diameter of an Optical Telescope Will