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pivoxa15
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Since the nucleus of an atom is +charged and the electron is -charged, why doesn't at least one electron fall into the nucleus?
Dr.Brain said:, thus it on the otherside rotates around the nucleus preserving the minimum quanta of energy it can hold in its state.Since there is a minimum 'quanta of energy' of the atomic orbital the wavefuntion of electron satisfies , it remains in that state and doesnot fall...
pivoxa15 said:Bohr couldn't explain the quantised angular momentum which lead to the quantised energy levels either.
From history it is known that to this question Born is answers by postulate (or axiom) that electron is not emitting the EM on stationary orbits. It is one of Born's postulates. Later, from quantum theory it is following that the electron is spread on whole orbit around the nuclei because nothing emits EM.pivoxa15 said:Since the nucleus of an atom is +charged and the electron is -charged, why doesn't at least one electron fall into the nucleus?
marlon said:I don't understand. Quantisized L and energy are the basic assumption's of Bohr's model. This models "solves" the problems with electrons spiraling down towards the nucleus because of it's basic assumptions it was built from. This model is "wrong" because it assumes that electrons have circular orbits around the nucleus. This clearly contradicts with HUP. But than again, Bohr's model (from 1913) is about 13 years older than Schrödinger's work.
regards
marlon
michael879 said:well I know this isn't the answer your looking for, but forgetting all the quantum stuff, in a Newtonian world, the electrons wouldn't all fall into the nucleus either. the ones closer to the nucleus would repel the ones farther away.
no... the electrons don't orbit, they can't accelerate because accelerating charges produce light, which would slow the electrons down and they would spiral into the nucleus.Suedeos said:[random]
at post #2..
so it's kinda like how shuttles are in a constant state of freefall around the earth?
[/random]
pivoxa15 said:What I like to know is what is the current conventional reason given to why electrons does not stick to the nucleus. There is obviously an attractive force between them but what is cancelling this attractive force and keeping the electron from totally "falling" into the nucleus?
jtbell said:there is a small but nonzero probability that the electron can actually be inside the nucleus.
Ratzinger said:When an electron is more confined, it has a higher energy spread. Does that imply it is more energetic than a less confined? If so, why are the higher energy orbitals farther away from the nucleus and confine the electron lesser in space (why are higher orbitals larger in space)?
Edit: but wait, energy is quantised in atoms, so why talking about HUP here?
The question is still what keeps the electron such a far distance away from the nucleus.
jtbell said:[I have time for one last word while eating breakfast...]
Oddly enough, in the [itex]n=1[/itex] state of hydrogen, the most probable position of the electron is at the origin (the nucleus), whereas the most probable radius is at the Bohr radius [itex]a_0[/itex]! This is not a contradiction because there are many more positions that have [itex]r=a_0[/itex] than have [itex]r=0[/itex]. Therefore, even though the probability density (square of the wave function) is larger for [itex]r=0[/itex] than for [itex]r=a_0[/itex], the radial probabilty is larger at [itex]r=a_0[/itex]. Note the two different names for the quantities!
For the hydrogen wave functions and probability distributions, click here.
And my answer is still: the Heisenberg uncertainty principle.
I don't know anybody who answers to this question in literature. But it is clear that it is the minimum of action function S=T-U, where T - kinetic energy, U - potential energy. This minimum is S=h/2pi. We can consider as analog the system of two classical particles in the sphere with non-zero energy. The momentum of this particles is non-zero two. And this particles is not collide because they moving.pivoxa15 said:I was trying to say that Bohr couldn't come up with a reason why electrons were quantised in orbitals with quantised angular momentum. He just accepted them as axioms if you like.
What I like to know is what is the current conventional reason given to why electrons does not stick to the nucleus. There is obviously an attractive force between them but what is cancelling this attractive force and keeping the electron from totally "falling" into the nucleus?
pivoxa15 said:Since the nucleus of an atom is +charged and the electron is -charged, why doesn't at least one electron fall into the nucleus?
Zakk said:Is there a possibility that the electron is colliding into the nucleus all the time
and a new electron is spinning out of the collission ? If this is a continuous process then it also explains why the electron seems to be switching orbits
ZAKK
pivoxa15 said:Since the nucleus of an atom is +charged and the electron is -charged, why doesn't at least one electron fall into the nucleus?
JayAaroBe said:I've read all the threads relating to this question but my mind is just having trouble with the concept. Let's take the simplest case: a hydrogen atom with one proton and one electron. They have opposite charges and attract. If I think of each as a particle, then my mind wonders why wouldn't the two particles attract each other and come together and collide.
The only way I can make sense of it is as follows, and tell me if this is an okay way to think of it: the electron is not a particle, but rather a spherical cloud of charge. In this case, I think of it the electron not as a single point but rather as the atmosphere around a planet and the planet itself as the proton (I know the sizes are not to scale). This is the only way I can think of it that makes any sense to me and answers the question of why an electron is not pulled into the nucleus (the proton).
QuantumClue said:One explanation, I have heard prof. Hawking recite is that an electron cannot settle at the nuclei of atoms because that would give an electron a well-defined position. So the electron does not spiral to the nucleus because it is forbidden by the Uncertainty Principle.
JayAaroBe said:I've read all the threads relating to this question but my mind is just having trouble with the concept. Let's take the simplest case: a hydrogen atom with one proton and one electron. They have opposite charges and attract. If I think of each as a particle, then my mind wonders why wouldn't the two particles attract each other and come together and collide.
The only way I can make sense of it is as follows, and tell me if this is an okay way to think of it: the electron is not a particle, but rather a spherical cloud of charge. In this case, I think of it the electron not as a single point but rather as the atmosphere around a planet and the planet itself as the proton (I know the sizes are not to scale). This is the only way I can think of it that makes any sense to me and answers the question of why an electron is not pulled into the nucleus (the proton).
JayAaroBe said:Could you address the bolded part of my post?