Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: hamza on 29/06/2009 20:06:44

Title: Energy query!!
Post by: hamza on 29/06/2009 20:06:44
hi.. i was thinking lately that there is a loss of energy everywhere, everytime, in the form of heat, light and different other forms.. but still things exist. I mean take an atom for instance. would'nt there be heat loss in the revolutions of an electron.. so when is it that an atom would die out ultimately.. i am aware of the phenomena that an electron would come to a lower energy level after losing some energy, but what if all it's energy is ultimately waived off. take this to a higher scale and consider large objects like the earth of ours, even WE, ourselves becoming short of energy ultimately...
 the question is do things die out after all there energy is gone?? i have a diagram below! 



 
Title: Energy query!!
Post by: Vern on 29/06/2009 21:33:55
As far as anyone can figure out, an electron does not lose energy due to its interaction within an atom. So we guess that things don't just run down and stop.
Title: Energy query!!
Post by: lyner on 29/06/2009 23:05:32
???
An electron 'can' lose ALL of its KE when it interacts with an atom.
The actual amount of energy lost will depend upon the precise situation and will involve a photon exchange- is the current theory.
Title: Energy query!!
Post by: Vern on 30/06/2009 00:10:34
An electron in an atom doesn't lose its energy and spiral into the nucleus. Of course an electron external to an atom can lose energy in an interaction; but that was not the subject in the op.
Title: Energy query!!
Post by: anerratic on 13/07/2009 02:15:30
Hi Hamza.

in response to your question, yes, we are experiencing a 'loss' of energy. This is mainly because of the second law of thermodynamics, which states that heat will always travel to a colder place. However, Matter is a very compact form of energy. This means that the energy stored in matter will only be released in fission or fusion or another type of decay. The sun releases heat energy by nuclear fusion, which converts mass into other forms of energy, including EM radiation and heat. However, energy cannot be created or destroyed (the 1st law of thermodynamics). This means that high-energy gamma rays can transform into a particle and it's anti-particle.

The second law of TD, which i think you may have been referring to in your post, is a grim forecast of what may happen to our universe if there is no 'big crunch' ending; eventually, when the stars have converted most of their lighter elements in the fusion process, The heat energy released will spread to fill space (which is only a few degrees above as cold as anything can possibly get - absolute 0 or -273.16°C).

I dont believe an atom could lose it's rest energy (the energy given by E=MC2 only)unless by nuclear fission or fusion. Having said that, some scientists theorize that the mean lifetime of a proton is >2.1x10^29 years (or there abouts).
Title: Energy query!!
Post by: Soul Surfer on 13/07/2009 08:29:40
The energy in the universe is NEVER LOST  It is simply moved about.  One of the most fundamental scoentific laws is the law of conservation of energy

The energy loss we experience in normal life is not in fact a loss of energy but smearing it out.  space is a very large and cold place and can easily loose all the heat of the sun spread out so it doesn't get significantly warmer than the cosmic microwave background at a few degrees above absolute zero.

In the case of normal atoms the electrons cannot lose any more energy because they are already in the lowest possible state and quantum mechanics forbids the loss of energy by tiny amounts only by specific jumps
Title: Energy query!!
Post by: lyner on 13/07/2009 09:19:16
Is it valid to apply basic laws of thermodynamics in non-thermodynamic situations? Afaik, thermodynamics applies on the macroscopic scale. Is it valid to include E=mc2 and QM considerations, willi nilli and to expect the right conclusions?