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:
- Kinetic energy of emitted electrons are found to be independent of intensity of incident light.
- Below a certain frequency (threshold) there is no photo-emission.
- Spontaneous emission of photoelectrons.
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