Electron Orbits and Gravity
RE: Electron orbital paths around a nucleus in a
Do electrons maintain a "constant" circular path around a nucleus when
travelling in the Y plane, I.E. vertically. or does a "Kepler" effect
start up where it would tend to accelerate towards the lower portion of
its orbit (due to gravity) and then slingshot back up?
The force of gravity depends upon the masses of the objects. Electrons and
atomic particles have such small masses gravity has a negligible effect on
their behavior under ordinary conditions. Electromagnetic forces and quantum
mechanics determine the behavior of atomic and subatomic particles.
The gravitational force acting on an electron is so small that it is
impossible to produce any observable effect, except perhaps in the bowels of
a black hole.
To illustrate, the gravitational force between the electron and the proton in
a hydrogen atom is approximately 1.0E-44 times smaller than the electrical
force. That's 0.000...0001 times, where there are 43 zeros between the
decimal point and the 1.
It is possible to have an analogous effect to the gravitational effect you
described by imposing a very strong electric field on the atom. This is
called the Stark Effect. It causing broadening and small shifts in the
spectral lines emitted by the atom. Do a web search on "stark effect" for
Best, Dick Plano...
Gravity effects are so much smaller than the other forces keeping an
atom together that on this scale, this small an object, they do not
matter. it is only when things get really big, with all the +/- charge
effects cancelling, but gravity continuing to "add up" that gravity matters.
A true electron orbit is not nearly so simple as a circle or ellipse.
According to quantum physics, there is no set motion. We can talk about an
average radius of an orbit. We can talk about the angular momentum and
energy of an orbit. We can talk about how much of the orbit is in the
horizontal plane. In reality, the electron's orbit is not any specific
motion. It bounces all over the place. Higher energy electrons have a
greater average radius. Different electrons have different angular
momentums. Exact path cannot be determined.
Dr. Ken Mellendorf
Illinois Central College
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Update: June 2012