An astronomer observes two stars of the same surface temperature, but one has twice the diameter of the other. How many times larger is the energy production rate per unit surface area from the larger star compared with that from the smaller star?
A) 2
B) 4
C) 16
D) They are the same.

Question

Quizplus · Accepted Answer

The energy production rate per unit surface area of a star is determined by its surface temperature, not its size. Since both stars have the same surface temperature, their energy production rates per unit surface area are the same.

An Astronomer Observes Two Stars of the Same Surface Temperature