Electrons are emitted from the surface when green light is incide… - Vidyadip

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

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

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