(N/A) The collector $(A = \text{anode})$ is kept at a positive potential with respect to the emitter $(C = \text{cathode})$, so that the emitted electrons are attracted toward the collector $A$.
By keeping the frequency of the incident radiation and the potential difference between the collector and emitter constant, the intensity of the incident radiation is varied, and the resulting photoelectric current is measured.
Experimental observations show that the photoelectric current is directly proportional to the intensity of the incident radiation.
This indicates that the number of photoelectrons emitted per second is directly proportional to the intensity of the incident radiation, as shown in the graph.