When a body is in thermal equilibrium with its surroundings, the absorptivity and the emissivity of the body are same. This Law is known as
A)Wein's Law
B)Kirchhoff's law
C)Stefan Boltzmann's law
D)None of the above
E)Nichrome

Question

Quizplus · Accepted Answer

Kirchhoff's law states that at thermal equilibrium, the emissivity of a body (or surface) equals its absorptivity in a given environment. This principle is fundamental in understanding how objects emit and absorb thermal radiation at the same temperature as their surroundings.

When a Body Is in Thermal Equilibrium with Its Surroundings