Black body radiations are:
Correct answer: B. All radiations
- A. Infrared and visible light rays
- B. All radiations
- C. Visible light and ultraviolet rays
- D. Ultraviolet and X-rays
Explanation
Black body radiations refer to the electromagnetic radiation emitted by a perfect black body, which absorbs all incident radiation and emits radiation across the entire electromagnetic spectrum.
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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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