Ions emitted from hot metals are called:
Correct answer: A. Electrons
- A. Electrons
- B. Protons
- C. Neutrons
- D. None of the above
Explanation
The process by which free electrons are emitted from the metal surface when external heat energy is supplied is called thermionic emission.
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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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