proper defination of saturation current and stopping potential?
The photo electrons emitted in photoelectric effect from cathode will be gained by anode to which positive potential is applied. If this positive potential is gradually increase photo electrons gained by anode also increases and reaches saturation state.i.,e with further increase of + ve potential to anode there will be no change in photo electric current. This maximum value of current is called "Saturation Current".
Now the potential of anode is to be reversed ( - ve ). If this negative potential applied to anode is gradually increased the number of photoelectrons reached to anode decreases and finally becomes Zero. " This reverse potential ( -ve)applied to anode where the photo electric current is zero is called Stopping Potential".