Photon Emission: Atom Collapse & Radial Forces Explained

[v_pino]

I'm sure I've heard the explanation for this before in class but I can't quite remember it:

If electrons of an atom emit photons (ie lose energy), the orbits of the electrons will become smaller, right?

If so, wouldn't the atom eventually collapse? What radially outward force keeps the atom from collapsing or what external energy excite electrons back to a higher state?

Also, wouldn't the attractive force between electrons and protons in the nucleus "collapse" the atom as well?

thanks

 

[ZapperZ]

Please start by reading the FAQ thread in the General Physics forum.

Zz.

 

[davenn]

hey Zapperz :)

reading that didnt really give me the answer I expected

to briefly answer v_pino's question in a basic way...

you have to take a step backwards... electrons don't just drop to a lower state, that is from the normal shell it resides into a lower shell.
Rather ... the addition of energy into the system will cause electrons to "jump" to a higher shell. Its when the electon drops back to its "normal" shell that it is loosing energy that is emitted as a photon (and prob other particles).

basic example... think of a neon sign or fluorescent lighting tube. energy in the form of electricity in being "injected" into the gas filled tube causing electrons of the atoms of gas to jump to higher shells as the electrons drop back down they emit photons and we see the light

so no spontaneously collapsing electron shells or atoms :)

cheers
Dave