Search results
Results From The WOW.Com Content Network
In photo electric effect K-shell electron is favoured because of the high electron cloud density in the K-shell. answered Apr 29, 2021 at 14:56. 33 4. Add a comment. Most Photoelectric interactions occur in the K shell because the density of the electron cloud is greater in this region and a higher probability of interaction exists.
The photoelectric effect is one of the physical phenomena that made necessary the introduction of quantum mechanics, a new theory. The other two are the black body radiation, and the atomic spectra. The photoelectric effect is the puzzle of why below a certain frequency the intensity of light cannot raise photo electrons.
At low energies, the photoelectric effect is the dominant effect. From about 200 keV to about 10 MeV, Compton scattering is the dominant effect. Above 10 MeV, the dominant effect is pair production. At a given photon energy, the relative probability of two processes would be the ratio of their cross sections.
It is thus possible to have a photoelectric effect, but would require photons with ten times more energy than for insulators. The outer electrons in insulators tend to have higher binding energies, so it requires more photon energy to free the electron. So, the photoelectric effect is still possible in insulators, it's just harder.
In the photoelectric effect however the photon seems to give all it's momentum and energy to the electron? No, the photoelectrons are emitted with a range of energies. The well known expression: $$ E = h\nu - \phi $$ gives the maximum energy, but photoelectrons are emitted with energies ranging from zero to this maximum value.
The photoelectric effect could be a contributor to the necessary absorption processes required for something to be considered an approximation to a blackbody. If that were the case then the rate at which electrons were being liberated would be in equilibrium with the inverse process - known as photo-recombination, where a free electron is ...
In the photoelectric effect, photons incident on the cathode cause the emission of electrons. Assuming there is a sufficient electric field, these electrons will make their way across to the anode, contributing current. For simplicity, let's assume every photon generates a photo-electron.
1. In the simplest of terms: It is the kinetic energy of an individual photon that determines whether a single photoelectron is released. So it is the number of photons (Intensity) with appropriate kinetic energy that affects photocurrent and the kinetic energy of a photon is proportional to its frequency. Share.
In a particular textbook, the work function of a metal (in the context of the photoelectric effect) is defined as: the minimum amount of energy necessary to remove a free electron from the surface of the metal. This sounds similar to ionisation energy, which is:
There have been attempts to describe the photoelectric effect by taking the EM field as a classical wave. For a discussion see a previous question "Can the photoelectric effect be explained without photons?". One of the answers describes that the photoelectric effect can be well explained considering the EM field more or less as a classical wave.