You can perform a simulated photoelectric effect experiment with this java applet.
You can adjust 1. photon energy 2. light intensity 3. work function of the metal and 4. the voltage of the circuit (can be positive or negative).
The I-V current will be shown. The default mode is auto (The voltage of the circuit will start from cutoff voltage  and increase with 0.3V every 10 seconds.) .
The simulation will be paused when it is more than 2.5 V.
You can adjust one of the parameters and press the play button again.

You can turn off "auto" mode and try the experiment by yourself,too.

translate strings in simulation to different language format before download
Full screen applet or Problem viewing java?Add http://www.phy.ntnu.edu.tw/ to exception site list
Press the Alt key and the left mouse button to drag the applet off the browser and onto the desktop. This work is licensed under a Creative Commons Attribution 2.5 Taiwan License
Download EJS jar file(1456.9kB):double click downloaded file to run it. (247 times by 96 users) , Download EJS source (66 times by 32 users) View EJS source