Q.
Anode voltage of a photocell is kept constant. The wavelength λ of the light falling on the cathode is being slowly modified. The variation of plate current I of the photocell will be ?
As λ is increased, there will be a value of λ above which photoelectrons will cease to come out so photocurrent will become zero.
As λ is decreased, the photoelectric current again decreases and other phenomenon as pair production starts dominating. Hence this graph is correct