Radiations are _ by a black body.
Correct answer: B. Both of these
- A. Absorbed
- B. Both of these
- C. Emitted
- D. None of these
Explanation
A black body absorbs electromagnetic radiations and then emits electromagnetic thermal radiations (also known as black body radiations) according to its temperature. Note that a good absorber is also a good emitter. An ideal system, or a black body, in this case, is a perfect absorber as well as a perfect emitter of electromagnetic radiations.
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About Dawn of Modern Physics
Classical physics cannot explain blackbody radiation and related observations, leading to Planck’s quantum theory, in which energy is emitted or absorbed in discrete packets. Photons provide the particle model of light, with energy and momentum linked to frequency and wavelength, including the photoelectric effect and its threshold frequency.
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