Question

Draw a plot showing the variation of photoelectric current with collector plate potential for two different frequencies, v₁ > v₂, of incident radiation having the same intensity. In which case will the stopping potential be higher? Justify your answer.

Answer 1

Effect of frequency of the incident radiation:

Taking radiations of different frequencies but of same intensity, the variation between photoelectric current and potential of plate A is obtained and shown in graph given below:

From the graph, we note:

(i) The value of stopping potential is different for radiation of different frequency.

(ii) The value of stopping potential is more negative for radiation of higher incident frequency.

(iii) The value of saturation current depends on the intensity of incident radiation, but is independent of the frequency of the incident radiation.