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PhysJs
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First of all, I would like to apologize if this question is in the wrong section of the forums. I'm not sure if the photoelectric effect should go into "Quantum Physics", "Classical Physics" or even "Homework & Coursework Questions"
Descriptions of the photoelectric effect commonly states the fact that ,provided the frequency of the light incident on the metals surface is more than the threshold frequency, the photoelectrons emitted have a range of kinetic energies, below and up to the maximum kinetic energy.
Question
My question is, why does the electrons have a range of kinetic energies? I am confused because I have heard 2 separate explanations of why there is a range of kinetic energies for the photoelectron:
Explanation 1): The electrons in the atom of the metal occupy different energy levels, thus have different minimum energy required to be "ejected" from the atom. So if two electrons occupying different energy levels absorb energy from a photon of the same frequency, the electron occupying a higher energy level in the atom will have a higher kinetic energy, while the electron occupying the lower energy level will be emitted with lower kinetic energy since it required more energy to be "ejected" from the atom.
Explanation 2): The electron might not be emitted from an atom at the surface of the metal, rather it could be somewhere within the metal. Therefore, the emitted electron has to pass through some portion of the thickness of the metal to exit the metal. In the process, it loses energy (Maybe because it bumps into/repelled by the electrons in the other atoms?)
Which, if any, is the correct explanation as to why emitted photoelectrons have a range of different kinetic energies?
Possible explanation?: "An electron to which kinetic energy has been imparted in the interior of the body will have lost some of this energy by the time it reaches the surface."-paragraph 3, no.8, pg13 of the document ,http://www.esfm2005.ipn.mx/ESFM_Images/paper1.pdf"
The above extract from a English translation of Albert Einstein's "Concerning an Heuristic Point of View Toward the Emission and Transformation of Light" seems to suggest Explanation 1). EDIT: Sorry typed wrongly when I posted this. seems to support Explanation 2), not 1).
Thank you for the attention,
PhysJs
EDIT:restored a spacing that I accidently removed when quoting "Concerning an Heuristic Point of View Toward the Emission and Transformation of Light". And I type the wrong possible explanation.
Descriptions of the photoelectric effect commonly states the fact that ,provided the frequency of the light incident on the metals surface is more than the threshold frequency, the photoelectrons emitted have a range of kinetic energies, below and up to the maximum kinetic energy.
Question
My question is, why does the electrons have a range of kinetic energies? I am confused because I have heard 2 separate explanations of why there is a range of kinetic energies for the photoelectron:
Explanation 1): The electrons in the atom of the metal occupy different energy levels, thus have different minimum energy required to be "ejected" from the atom. So if two electrons occupying different energy levels absorb energy from a photon of the same frequency, the electron occupying a higher energy level in the atom will have a higher kinetic energy, while the electron occupying the lower energy level will be emitted with lower kinetic energy since it required more energy to be "ejected" from the atom.
Explanation 2): The electron might not be emitted from an atom at the surface of the metal, rather it could be somewhere within the metal. Therefore, the emitted electron has to pass through some portion of the thickness of the metal to exit the metal. In the process, it loses energy (Maybe because it bumps into/repelled by the electrons in the other atoms?)
Which, if any, is the correct explanation as to why emitted photoelectrons have a range of different kinetic energies?
Possible explanation?: "An electron to which kinetic energy has been imparted in the interior of the body will have lost some of this energy by the time it reaches the surface."-paragraph 3, no.8, pg13 of the document ,http://www.esfm2005.ipn.mx/ESFM_Images/paper1.pdf"
The above extract from a English translation of Albert Einstein's "Concerning an Heuristic Point of View Toward the Emission and Transformation of Light" seems to suggest Explanation 1). EDIT: Sorry typed wrongly when I posted this. seems to support Explanation 2), not 1).
Thank you for the attention,
PhysJs
EDIT:restored a spacing that I accidently removed when quoting "Concerning an Heuristic Point of View Toward the Emission and Transformation of Light". And I type the wrong possible explanation.
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