Photoelectric Effect Applet
But how does this demonstrate that light is a
particle?
Well, if light was strictly a wave, then increasing the
intensity (brightness)
of the light should increase the energy and number of
electrons emitted
However, only the number of electrons increases. The energy
of the
electrons do not increase.
In a certain material like
Sodium, an intense bright red light will be unable
to emit any electrons, but a very dim blue light would be
able to.
How do we explain that?