Posted: Apr 29, 2017 10:22 am
LjSpike wrote:Cito di Pense wrote:LjSpike wrote:Cito di Pense wrote:
What's the intensity of the radiation? Some measure of the flux of energy normalized on a unit area. More photons per second per unit area, more photoelectrons. If something is varying in time or space (like your photoelectric example -- something resulting in more -- or fewer -- electrons emitted per second) then you can refer to the amplitude of the variation, and refer it to some base. Measurement units like MKS or CGS can be referred to as 'dimensions' of a problem, but only the distance units (meters or centimeters) reference an explicitly 'spatial' dimension.
You could vary the 'amplitude' of the incoming radiation by orienting the incoming beam obliquely. This affects the flux, too.
That was a rather jargon filled comment. Perhaps try simplifying it a tad?
It would be better if you would restate your first remaining question. Do some more reading on the photoelectric effect and see if you can focus your question a little more. Don't try to address the photoelectric effect with wave theory. It's a photonic phenomenon, and one of the early results that finally led to a formal quantum theory of light and matter.
It's not a photonic phenomenon nor is it a wave phenomenon, it's simply that we try to address it as one or the other as we can't get our heads around it being both. There is no reason to not attempt to explain it as a wave phenomenon, if one can achieve such an explanation. After all, light has switched back and forth between being explained as photons and waves in the past, first with Newton I believe, stating it as particles, then to waves, then back to photons.
I also believe It's also been determined that huge amplitudes can cause emission below the threshold frequency, which wouldn't settle down too nicely with the current explanation of how it works with photons as in that case the frequency should be the determinant factor in energy passed on (and therefore emission).
Simply put though, the point which I can't get to properly explaining is why an increase in amplitude increases photoelectrons emitted per second. I presume in a photonic interpretation one would state amplitude increases causes more photons to hit the surface per second, however with wave theory I can't quite work out an even tangible explanation. On the other hand, I can at least begin to explain why huge amplitudes would cause emission at lower frequencies...
Now I could read through tonnes of scientific papers to try and work out what was meant in that previous comment, however I'd have to go through tonnes before I found some that were less heavy on jargon, and I can't ask them to rephrase it, unlike here, I can ask for some rephrasing and/or analogies to help me understand the points presented.
You're right, Spike. Greater numbers of incident photons above the threshold frequency will increase emission of photoelectrons.
What will you have when you finally understand, Spike? What will you have when you can make up answers for your own 'why' questions, such as why huge amplitudes would cause emission at lower frequencies (based on sources you have yet to cite)? Will you ever be able to just shut up and calculate? Read a fricking textbook on quantum mechanics, but learn about vectors and matrices first.
I tried to get you to think about it in terms of magnitude or intensity (of a radiation field) instead of amplitude (which you may be confusing with probability amplitude, but I have no way of knowing, the way you're thrashing around, here as you continue to try to apply wave phenomena to the photoelectric effect because you read somewhere (and haven't cited it) that "it's been determined that huge amplitudes (sic) can cause emission below the threshold frequency". Yes, Spike, photons have frequencies, and photonic processes have statistics. When you're ready to learn something, begin at the beginning.
You could start with the wikipedia article on the photoelectric effect. I quote:
Below that threshold, no electrons are emitted from the metal regardless of the light intensity or the length of time of exposure to the light (rarely, an electron will escape by absorbing two or more quanta.