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The statement that a good absorber of radiation is also a good emitter is explained by:

1. Stefan's law
2. Kirchhoff's law
3. Newton's law of cooling
4. Wien's displacement law

Correct answer: Kirchhoff's law

Solution

Kirchhoff's law of thermal radiation states that for a body the emissivity equals the absorptivity, so good absorbers are good emitters.

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