Question

26) Star A and star B are the same surface temperature. Star A has twice the radius as star B. How does the amount of energy radiated per unit area from the surface of A compare to surface of B?

Answer 1

Answer:

1/4

Explanation:

Total radiation energy depends on temperature, so $E_A=E_B$

Radius $R_A=2R_B$

so the surface area $S_A=4 S_B$

energy per unit area

$\frac{E_A}{S_A}=\frac{1}{4}\frac{E_B}{S_B}$