Minimum energy required to eject an electron from metal surface is called:
Correct answer: C. Work function
- A. Stopping potential
- B. Electromotive force
- C. Work function
- D. Threshold frequency
Explanation
The work function is the minimum energy needed to remove an electron from a solid to a point in the vacuum immediately outside the solid surface. Stopping potential is defined as the potential required to stop ejection of electrons from a metal surface when an incident beam of energy greater than the work potential of metal is directed on it. Threshold frequency is the minimum frequency of incident light that can cause emission of electrons from the metal surface.
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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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