Compton Scattering in Laymen's terms

[StephenP91]

I just need an explanation of this. Found it in a question.

Also, photons when absorb by an electron in an atom, does the energy (if less than the ionisation energy) have to be exactly equivalent to one of the energy states and if it isn't what happens?

You probably think I suck at Physics. You're right.

Thank you,
Stephen.

 

[diazona]

Umm... you really haven't given us (me) any reason to think you suck at physics

Also, photons when absorb by an electron in an atom, does the energy (if less than the ionisation energy) have to be exactly equivalent to one of the energy states and if it isn't what happens?

To be perfectly honest, I'm not sure what that's trying to say.

 

[StephenP91]

To be perfectly honest, I'm not sure what that's trying to say.

Well, in the Photoelectric effect, when electrons get excited to a higher energy level when they attain some sort of energy. In the case of absorbing a photon, does the requisite energy (hf) have to be equal to the energy of one of the energy states.

The reason I ask this is because, on the marking scheme, one of the answers is that:

"A photon can lose all of it's energy, but not part of it"

Though, when I was reading about that Compton Effect I read something about absorbing part of it. So I am pretty darn confused.