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My teacher says one thing, text book says otherwise...help (physics)

(This bout energy levels n dat) basically what happens if an atom gains enough energy to move it up to the the next shell but the energy gained is a bit more then required?
So easy e.g. if 6eV is required but it gains 7eV and the next shell up is let's say 7eV

Srs if that makes no sense😅😅
Reply 1
The electrons in the atom will move between energy levels ONLY if they gain the specific amount of energy to move from one level to another (or enough energy to leave the atom completely). If two of its energy levels are 6eV and 7eV higher than the ground state and an electron gains 7eV, the electron will move to the 7eV energy level. If it gains 6.5eV for example, it won't be excited and move higher at all.
Reply 2
Original post by yngze
The electrons in the atom will move between energy levels ONLY if they gain the specific amount of energy to move from one level to another (or enough energy to leave the atom completely). If two of its energy levels are 6eV and 7eV higher than the ground state and an electron gains 7eV, the electron will move to the 7eV energy level. If it gains 6.5eV for example, it won't be excited and move higher at all.


ok safe, thats what my teacher said, however my textbook mentions inelastic scattering, can you explain this if you know?
Reply 3
Idk our teacher mentioned it too but I don’t remember what it was. Its not on the spec so I think it’s more of a wider knowledge kinda thing than something we actually need to know.
Original post by forre
(This bout energy levels n dat) basically what happens if an atom gains enough energy to move it up to the the next shell but the energy gained is a bit more then required?
So easy e.g. if 6eV is required but it gains 7eV and the next shell up is let's say 7eV

Srs if that makes no sense😅😅

Question your teacher on this. Sometimes teachers are know to make mistakes. Textbooks are also known to make mistakes.
Original post by forre
ok safe, thats what my teacher said, however my textbook mentions inelastic scattering, can you explain this if you know?


Can you give more detail about what your textbook writes about inelastic scattering? Inelastic scattering of photon or electron?
Reply 6
Original post by Eimmanuel
Can you give more detail about what your textbook writes about inelastic scattering? Inelastic scattering of photon or electron?


it states 'the energy of the incident elsoctron is greater thjan the energy gap between allowed orbits. some of the energy of the incideint electron transfers to the atomic electron, raising it to a higher energy level'

what happens to the energy the atomic electron doesnt absorb? lol im confussed
In this case we are firing an electron at an atom, where the incident electron has a kinetic energy that is greater than the energy gap. The incident electron is scattered off the atom and loses kinetic energy; the lost energy is transfered to the atom and is used to raise the atomic electron to a higher energy level. The main point is that there is an outgoing electron (as it is a scattering process) which takes away some of the energy.

This is different from the case of a photon hitting an atom, where generally the photon will be completely absorbed. In this case the photon needs to have exactly the right energy (to move an atomic electron between energy levels), otherwise it won't be absorbed at all.

So in my view, both the teacher and the textbook are correct.
Original post by forre
it states 'the energy of the incident elsoctron is greater thjan the energy gap between allowed orbits. some of the energy of the incideint electron transfers to the atomic electron, raising it to a higher energy level'

what happens to the energy the atomic electron doesnt absorb? lol im confussed



I think the textbook is describing what is known as Franck-Hertz Experiment. I agree with what Theory321 described in post #8.

I remembered asking the lecturer during my university study a “stupid” question about the Franck-Hertz Experiment how does the incident electrons “know” how much to transfer to the target atom orbital electron? :smile:
Reply 9
Original post by Theory321
In this case we are firing an electron at an atom, where the incident electron has a kinetic energy that is greater than the energy gap. The incident electron is scattered off the atom and loses kinetic energy; the lost energy is transfered to the atom and is used to raise the atomic electron to a higher energy level. The main point is that there is an outgoing electron (as it is a scattering process) which takes away some of the energy.

This is different from the case of a photon hitting an atom, where generally the photon will be completely absorbed. In this case the photon needs to have exactly the right energy (to move an atomic electron between energy levels), otherwise it won't be absorbed at all.

So in my view, both the teacher and the textbook are correct.


ohhh rightt, safe my guy

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