Absorbed photons, emmited photons

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Homework Statement



how can i tell if a photon is being emmited or absorbed?

Homework Equations



hc/lambda= energy per photon
1/lambda=r(1/n^2-1/k^2)

The Attempt at a Solution



photons are absorbed when the energy of the photon= energy of transition?
when are they emmited?
and i thought that energy of photon was always = to energy of transition so I am a bit confused.
for example, A photon with λ = 600 nm interacts with a hydrogen atom in fundamental state is the photon absorbed? how can i see whether it is or not?
i know fundamental state is k=1 but i don't know how i can see whether it is being absorbed or not
 
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That's an easy one: When a photon is absorbed it promotes the atom to a higher energy state. So absorption takes place when the final state is higher than the initial state. When a photon is emitted it is a de-excitation of the atom. That is, the atom goes from a higher state to a lower state.

If the initial state is k=1 then the only thing the atom can do is absorb a photon. It can't de-excite to a lower energy level because there's nowhere for it to go.
 
o ok.
but if k=1 and i get n=1.08 and since only integers are accepted would it round off to 1 and not absorb? or since it is a larger number than 1 it would absorb?

btw
if it absorbs, would the rest of the energy that was left that didnt absorb turn into kinetic energy?