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

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsDual Nature of Radiation and Matter2 Marks
Question
Electrons are emitted from the surface when green light is incident on it, but no electrons are ejected when yellow light is incident on it. Do you expect electrons to be ejected when surface is exposed to (i) Red light and (ii) Blue light?
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Answer

  1. The wavelength of red light is longer than threshold wavelength, hence no electron will be emitted with red light.
  2. The wavelength of blue light is smaller than threshold wavelength, hence electrons will be ejected.

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