Question

Electrons are emitted from a photosensitive surface when it is illuminated by green light but electron emission does not take place by yellow light. Will the electrons be emitted when the surface is illuminated by (i) red light, and (ii) blue light?

Answer 1

Ejection of electrons will be possible by radiations of wavelength less than that of green light. Because, λb < λg wavelength of blue light is less than the wavelength of green lights

So the answer is blue light