My friend recently said that the electrons spinning around an atom are in perpetual motion and violate the laws of thermodynamics. True?
No, not true.
From what I understand, electrons orbiting an atom are not in perpetual motion becuase they are constantly receving energy from outside sources, collisions with other atoms, heat etc…which keeps them going therefore they do not break any of the laws of thermaldynamics.
Well, they are in perpetual motion, but don’t violate the laws of thermodynamics.
Electron motion is nothing like planetary motion, but you could say the earth is in perpetual motion around the sun and doesn’t violate the laws of thermodynamics. Or the whole galaxy is in motion and doesn’t violate the laws of thermodynamics.
It would only violate thermodynamics if you could extract energy from the electron motion without reducing its orbital energy. Electrons are for other reasons only allowed to exist in certain predefined energy levels. At the lowest level (ground state), no energy may be recovered from them. The remain in perpetual motion and thermodynamics is still preserved.
Should be good enough for a laymen explaination. You can get a better picture by looking at thermodynamics and basic atomic theory. Not too hard really.
If electrons were little point sources in determined orbits around the nucleus and were emitting energy, they would be perpetual motion machines. The indeterminancy of quantum mechanics in terms of position and velocity provides a side benefit of getting rid of this classical interpretation.
Note that “Perpetual Motion Machines” violate the laws of thermodynamics. That is, a device that runs forever and generates power. Since an electron doesn’t generate power all by itself, it is not a machine.
Believe it or not, Scientists already have simple answers for these an amazing number of other lame questions you friend has.
To expand a bit on what mipsman said, electrons are not little point particles. The picture of an electron orbiting a nucleus like the moon orbiting the earth is wrong. Electrons more closely resemble fuzzy smears of charge surrounding a nucleus.
In any case, as already mentioned, this has nothing to do with perpetual motion or thermodynamics. Something can be in motion forever, it just can’t do any work.
They dont collide with anything to generate friction like gears or something would. They exist in a vacuum. Hence they are in perpetual motion.
Why is it that snotty replies so often contain grammatical errors?
Peace,
mangeorge
I believe that’s a corollary to Gaudere’s Law.
Actually, electrons are point particles, and no measurement has ever shown them to be otherwise. When the term electron cloud is used it is referring to the probability distribution of finding an electron in a unit volume ala Born’s interpretation of the Schrodinger equation.
Even though electrons don’t have orbits they do have orbital angular momentum which is but one of the many strange manifestations of quantum mechanics. A reasonable man of ordinary prudence would think that a particle with orbital angular momentum would be orbiting something, but ……and so it goes.