Einstein's ideas applied to the photoelectric effect
By the early 1900ís, the photoelectric effect had been very well researched, but it remained unexplained.
Then along comes Einstein, with a mighty pen in hand, to save the day!
Einstein liked Planckís idea that radiation was made up of particles of a quantized energy, and he extended this idea so that it included light. Then he took this new view of light and applied it to the photoelectric effect experiment that was performed by Lenard.
So letís see what happens when we try to explain the photoelectric effect by treating light as a particle instead of a wave.
Follow the steps below and watch what happens!
1- Click the start button to see the particles of light begin to flow.
2- Pick a metal of your choice from the pull-down menu. Different metals will give different stopping potentials.
3- Slowly decrease the wavelength of the light. Eventually you will see that electrons will begin to come off of the negatively charged plate.
4- Click the intensity button (at the top of the applet) and noticed that each extra photon striking the plate produces an extra electron.
by Phillip Warner
You can view a summary in lay terms of Einstein's original paper. (divided into 3 parts)
Chapters 1 to 3, by Yann Gagnon
Chapters 4 to 6, by Atri Maharaj
Chapters 7 to 9, by Sean Sutton