Question
Question: A ball of surface temperature T is in thermal equilibrium with its environment of constant temperatu...
A ball of surface temperature T is in thermal equilibrium with its environment of constant temperature. Which of the curves in figure gives the energy E radiated by the sphere versus time t:
A
1
B
2
C
3
D
4
Answer
2
Explanation
Solution
As the body is in thermal equilibrium with the environment then it must radiate at constant rate, that is equal to rate of absorption so as to keep its temperature constant. Thus E ∝ t.