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Dual Nature of Radiation and Matter — Physics STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 SciencePhysicsDual Nature of Radiation and Matter3 Marks
Question
Write three characteristic features in photoelectric effect which cannot be explained on the basis of wave theory of light, but can be explained only using Einstein’s equation.
✓

Answer

The three characteristic features which can’t be explained by wave theory are:
  1. Kinetic energy of emitted electrons are found to be independent of intensity of incident light.
  2. Below a certain frequency (threshold) there is no photo-emission.
  3. Spontaneous emission of photoelectrons.

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