Which of the following statement is correct?

(a) Photo current increases with intensity of light

(b) Photocurrent is proportional to the applied voltage

(c) Current in photocell increases with increasing frequency

(d) Stopping potential increases with increase of incident light

(a)

According to photoelectric effect, speed of electron (kinetic energy) emitted depends upon frequency of incident light while number of photoelectrons emitted depends upon intensity of incident light. Hence, as the intensity of light increases, the photocurrent increases. In a photo-cell, the photocurrent has no relation with the applied voltage.

Stopping potential is the (negative) potential at which the current is just reduced to zero. It is independent of intensity of light but depends on the frequency of light similar to K.E.