Two heated spheres are at the same temperature, but one sphere has twice the radius of the other. The flux emitted from the larger sphere is
A) half the flux emitted from the smaller sphere.
B) the same as the flux emitted from the smaller sphere.
C) twice the flux emitted from the smaller sphere.
D) 4 times the flux emitted from the smaller sphere.

Question

Quizplus · Accepted Answer

The flux emitted per unit area (intensity) depends only on the temperature, not the size of the sphere. Since both spheres are at the same temperature, they emit the same flux per unit area.

Two Heated Spheres Are at the Same Temperature, but One