Jan Panteltje wrote:
On a sunny day (Mon, 22 Aug 2005 15:24:10 -0700) it happened Eugene
Stefanovich wrote in :


How would you explain the fact that when the frequency of the wave is
below the threshold, the ball will never leave the hole no matter
how high is the amplitude of the wave? That's what happens in real
photo-electric effect.

Eugene.

Hi, I have made a better model now, it is in an other post, marked
[More on: part 2] Explaining the photo electric effect from the wave perspective.
But as it is actually (in my view)an electromagnetic effect, I will repeat
that text here for you.
Pleae not also that in the case of the magnet, the amplitude makes no
difference, only the speed at which it moves (frequency).
So there is your threshold.

You probably wanted to say "acceleration at which it moves". Speed plays
no role here. Then please note that acceleration of periodic movement
is proportional to the amplitude b
(it is also proportional to the square of frequency f)

x(t) = b sin(ft)
v(t) = bf cos(ft)
a(t) = -bf^2 sin(ft)

So, if you keep the frequency constant and increase the amplitude
(use light of higher intensity), then at some point you should
reach the threshold acceleration and, therefore, electron emission.
This is not what happens in the photoelectric effect.
If the frequency of light is low, then no matter how high is the
amplitude (light intensity), you'll not see the electron emission.

Of course, at very high intensities you'll start to see the emission,
but this will be due to two-photon processes (electron absorbs two
photons at once) which have nothing to do with the "normal" situation
discussed here.

Eugene.