By what factor does the total energy emitted per unit time at all wavelengths from an opaque, perfectly absorbing object increase if its temperature increases by a factor of 3 (e.g., approximately from room temperature to 900 K)?
A) 27
B) 3
C) 9
D) 81

Question

Quizplus · Accepted Answer

The total energy emitted per unit time by a black body is given by the Stefan-Boltzmann law, which states that it is proportional to the fourth power of the temperature (T^4). If the temperature increases by a factor of 3, the energy emitted increases by 3^4 = 81.

By What Factor Does the Total Energy Emitted Per Unit