When a monochromatic point source of light is at a distance r from a photoelectric cell, the cut-off voltage is V and the saturation current is I. If the same source is placed at a distance 3r away from the photoelectric cell, then

When the distance is increased, frequency of incident light and hence the stopping potential does not change. But the intensity changes and hence the saturation current decreases nine times. 

[$\because$  Intensity of incident radiation   $\propto \frac{1}{{\text{ (distance) }}^2}$]