Internal motion of atoms and collisions

[Dr.Brain]

Main Question or Discussion Point

I was thinking , if we take into account oly the internal motion of atoms , all collisions will turn out to be elastic. Wont they be?

 

[Physics Monkey]

In quantum mechanics, photons can scatter off atoms inelastically in what is called a Raman process. Also, the technique known as deep inelastic scattering is a powerful tool for studying the structure of nuclei. So inelastic scattering can happen even at the quantum level.

 

[Dr.Brain]

I am talking at macro-level . The collisions which look to be inelastic viewed form outside due to merging of masses ( in the case of inelastic collisions in which the the two rigid bodies donot mix up after collision but retain their boundary even though they may change their shapes ), but their particles were not allowed to enter each other's boundaries , which would imply they retorted back after collision . At micro-level thsi would mean everything happened elastically even though from outside it appears to be inelastic.

(This thread I posted because I looked at collision from a different point of view..I am in no mood to change any laws...)

BJ

 

[shyboy]

It looks like you are trying to address the question how reversible mechanical laws produce irreversible thermodynamics...

 

[Antiphon]

I was thinking , if we take into account oly the internal motion of atoms , all collisions will turn out to be elastic. Wont they be?

Yes, but some of the collisions may make essentially irreverible changes
even though they are elastic. For example, if a collision is energetic enough
you could split an atom. While this is reversible in principle, it would be very
unlikely that you could put the atoms back the way they were. So in
practice there is effective irreverability even though each individual
transformation is reversible.