“A good absorber of a given wavelength of radiation is also a good emitter of that wavelength.” This is a statement of:

Stefan-Boltzmann's law
Wien's Law
Kirchoff's Law
The First Law of Thermodynamics E. The Law of Relativity

The correct answer is C. Kirchoff’s Law.

Kirchhoff’s Law states that at a given temperature, a good absorber of a given wavelength of radiation is also a good emitter of that wavelength. This is because the absorption and emission of radiation are both caused by the interaction of electromagnetic radiation with matter. When radiation hits an object, some of the radiation is absorbed and some of it is reflected. The amount of absorption and reflection depends on the properties of the object, such as its color and shape. Objects that are good absorbers of a given wavelength of radiation are also good emitters of that wavelength. This is because the same processes that cause absorption also cause emission.

Stefan-Boltzmann’s law states that the power emitted by a blackbody is proportional to the fourth power of its temperature. Wien’s law states that the peak wavelength of blackbody radiation is inversely proportional to the temperature. The First Law of Thermodynamics states that energy can neither be created nor destroyed, but can only be transferred from one form to another. The Law of Relativity states that the laws of physics are the same for all observers in uniform motion relative to one another.

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