Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: hamza on 21/12/2007 04:49:59

Title: Atomic energy
Post by: hamza on 21/12/2007 04:49:59
This question is related to the atomic structure. We all know that electrons are revolving around the nucleus of the atom, in fixed orbits (energy levels) and only those orbits are feasible that have certain angular momentum assigned to them and have specific energy.Here are a couple of questions; I was wondering where this assigned energy comes from. What is the energy source and why doesent the energy dissipate. If energy of higher orbits is released, they come to the lower orbits, but what if  the energy of the first orbit dissipated??
Title: Atomic energy
Post by: Soul Surfer on 21/12/2007 10:31:53
I agree it is a bit counter intuitive but the lowest pair of electrons just cannot loose their energy and collapse on to the nucleus except in very special circumstances.  That is when the nucleus desperately needs an electon a process called K capture and this is a weak interaction process not a pure electromagnetic one.

The reason is that electrons are very light and therefore have a big quantum mechanical uncertainty about where they are and how fast they are moving.  Normally the nucleus is far to small a place to restrain them so the lowest energy electons spend their time buzzing around in the vecinity of the nucleus they even spend some of the time inside the nucleus.  Remember electron orbitals are not neat orbits like planets but a probaboility fog showing the probability of finding an electron at a particular position with respect to the nucleus.

All this motion implies a certain amount of energy and that is determined by Plancks constant.