In the photo-electric effect, electrons are emitted on incidence of light upon certain material surfaces:
Correct answer: C. Above a certain frequency
- A. Below a certain frequency
- B. Beyond a certain wavelength
- C. Above a certain frequency
- D. None of the given options
Explanation
The photon energy must exceed the work function for electron emission.This is the correct answer.
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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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