Hello all,
My name is Vaj, and I am a first year mechanical engineering student.
My father and I started discussing the photoelectric effect a few days
ago and he mentioned how the thermoelectric effect seemed similar. In
delving further into the matter, we seemed to run into a problem of
sorts. As I know it the photoelectric effect is basically photons
striking the surface of a conductor and causing electrons in it to
scatter and escape the material, creating a current. The
thermoelectric effect, on the other hand, is caused by heat
differences in the material causing charge carriers that to diffuse to
opposite sides of the material, causing current.
But what is the difference here? Photons are made of energy. This
energy is absorbed by electrons and causes them to fling off of their
atoms or to simply get excited and then radiate that energy right
back. What is heat, though? It thought it was defined to be energy in
transit. Is that not the same as what photons are?
So now, my questions:
1. In the photoelectric effect, shouldn't the movement of electrons in
the material cause current, rather than their escape?
2. What exactly is the difference between photons and "heat"?
3. If they are not truly different, how do the two effects differ?
.
|
