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Inside an Atom

  1. Oct 5, 2003 #1
    Newbie here, so go easy. The electron contains a negative charge, the proton has a positive charge, so why is there no attraction between the two? Why doesn't the electron spiral towards the nucleus? The electron is an accelerating body, so why is no radiation being emitted?


    Thanks
     
    Last edited: Oct 5, 2003
  2. jcsd
  3. Oct 5, 2003 #2
    heres a question for you, why doesn't the Earth and all the planets fall into the sun instead of orbitting? what about the moon? and electrons are accelerating iirc, they're the exception in motion i think, probably due to they're sub-atomic nature

    atleast, thats what i think, someone could correct me if i'm wrong
     
  4. Oct 5, 2003 #3

    chroot

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    The planets don't fall into the sun because they have tangential velocity.

    The electrons don't fall into the nucleus because energy is quantized in potential fields.

    p.s. Don't cross post, sanjuro.

    - Warren
     
  5. Oct 11, 2003 #4
    The DO feel an attraction from eachother. A VERY[\B] LARGE ONE, and by classical calculations every atom in the universe should have sucked itself up into little neutron balls a fraction of a second after the universe was formed. Luckily for us it didn't.

    Electrons do wander into the nucleus from time to time. it is known as electron capture and creates neutrons(effectivly changing the atom into another element)

    the reason why the death-of-every-atom scenario didn't play out was explained by Bohr. Bohr's calculations use a quantized angular momentum for an electron. He did this for the same reason others where quantizing characteristics. to solve lingering problems, in this case the fact that the universe is still here.

    The problem is dealt with and exinguished when you start dealing with the statistical interpretations of the atom, because then electron are no longer spinging aroung readiating energy as they would in a classical sense.
     
    Last edited: Oct 11, 2003
  6. Oct 12, 2003 #5
    From my idea of gravity.

    If you had two hydrogen atoms, and they were a 100 yards apart, and thats all there was, and they were motionless in relationship to each other, and if the gravitational fields of these atoms were put in force - The two atoms would not collide but initially orbit.

    I look at gravity as mechanical. The field is like a gear where the teeth of a gear are the waves of the field, and when two waves mesh for an instant ... they push or pull accordingly, and when they do - it is not in the exact direction of the source of the gravitational fields.
     
  7. Oct 12, 2003 #6

    chroot

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    This is incorrect. The two particles initially have no angular momentum about their center of mass, and since angular momentum is conserved, they will always have zero angular momentum about their center of mass. The particles will not orbit, but will instead come directly together and collide.

    - Warren
     
  8. Oct 12, 2003 #7
    This is through you're interpretation, and of course others, and you have mine. It is doubtful that this has been tested, and it's unlikely it can be without interference from other sources.

    I'm simply saying there is a lateral component to fields, and a gravitational field is not an exception. You have yer numbers to go by. I have a plethora of bodies in space that happen to be in orbit. How they got that way is up for grabs as far as I'm concerned.
     
  9. Oct 12, 2003 #8

    chroot

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    The conservation of (angular) momentum has been tested hundreds of thousands of times.
    There is no debate about it. The orbiting bodies result from the fact that the fragments of collapsing gas clouds have non-zero initial angular momentum.

    - Warren
     
  10. Oct 12, 2003 #9

    russ_watters

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    Sorry, Arc - you're arguing against Newton's laws of motion and gravity and Einstein's gravity. And how they work is equisitely well understood and extensively tested. Not gonna win.
     
  11. Oct 13, 2003 #10
    You are perhaps misinterpreting the extent by which this lateral component effects the motion of bodies. It would be slight at best. Yet enough to establish a preference. Bodies rotate - galaxies rotate - there is a preference to the direction they rotate. It would be the lateral component of a gravitational field that establishes this.
     
  12. Oct 13, 2003 #11

    chroot

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    There is no such preference. If you want to say that a galaxy is rotating clockwise, for example, the alien people on the opposite side of it would see it rotating counter-clockwise. Who's right? Galaxies, you must realize, have angular momentum vectors that point in all directions, without any preference.

    You are correct in assuming that a very large cloud of gas, with billions of tiny individual atoms and molecules, will always have SOME initial angular momentum. Even if only one atom happens to be moving with some non-zero velocity tangentially to the center of mass, there is angular momentum. Given the normal thermal energies of a gas in intergalactic space, you can calculate the probability of a cloud having any particular angular momentum. As the cloud collapses, the angular velocities are "amplified," much as a figure skater pulls in her arms to spin faster. Even a very, very slight initial angular momentum is enough to make the cloud rotate rather briskly after it has collapsed 100,000-fold.

    Your assertion that the rotation is instead due to some peculiar "lateral component" of gravitation is wholly unsupported both experimentally and theoretically. Sorry.

    - Warren
     
  13. Oct 13, 2003 #12

    russ_watters

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    First you have to find some EVIDENCE of this lateral component of gravity - rotating galaxies aren't it. Second, you'll need to put together a theory on how it might work - our existing theories don't contain it. Lotta work to do before you can say things like this.

    Further, if there WAS a lateral component to gravitational attraction, we'd proabably already have seen it causing perturbations in orbits.

    So again:
     
  14. Oct 13, 2003 #13
    I thought it was because on that level, electrons are actually very very far away from the nucleus and so the attraction wasn't great enough across that huge distance to pull the electrons in. i don't realy know, but that's what i thought.
     
  15. Oct 13, 2003 #14
    They would both be absolutely correct. I'm assuming one side see's a mirror image of the other. Knowing this - It would be easy to agree they are seeing the same direction of motion.

    There are two choices for rotation - Thisaway -> and <-thataway. There must be a preference one way or the other established.
    A figure skater can spin faster, but must spin first in a chosen direction. I say this is no random act, but a choreographed display.

    You are correct - I did say this is (From my idea of gravity).

    Yep - lotsa work. Gonna say it anyway. Don't make it so ... does it?

    This idea is a product of mine own imagination. I let it take me anyplace, anytime, anyhow. Don't matter .. just as long as it runs wild.

    Actually the orbits would be just exactly as they are. The lateral component would determine thisaway or thataway. At least from my current understnding of mine own idea.
     
  16. Oct 13, 2003 #15

    chroot

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    No. The axial vector representing the angular momentum can point in any direction in three-space. There are an infinity of different choices.
    WHY must there be? Look around. It certainly seems that's not true.
    The figure skater is equally capable of spinning in either direction.

    - Warren
     
  17. Oct 16, 2003 #16

    turin

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    Maybe my university feeds us horseshait, and I wouldn't be surprised if this is so, so I won't mention the name of the institution. Anyway, we have this thing called "colloquium" that they make us go to that's required for grad students to be in "good standing" (I still haven't figured out what that means). At one of these colloquiums, we had a German scientist from Ulm (we get a lot of Ulmsters, I wonder if they're among the few willing to visit) come and talk about gyroscopic precession and that they wanted to lanch gyros into space and study what he called "gravitomagnetism," which was somewhat analogous to what the magnetic field is to the electric field.

    Just one more thing. I would be quite surprised if we eventually concluded that there is no cross term for gravitation.


    well I'll be screwed blued and tatooed, looks like they don't allow none of that there confounded devil speak in these parts!
     
    Last edited: Oct 16, 2003
  18. Oct 17, 2003 #17
    Sanjuro...

    Well, u have asked a question in a very classical manner. Since u say that u r a newbie, let me explain in a simple manner. There are what are called Stationary orbits in Quantum Mechanics. These are orbits where the Electrons are comfortable. They do not emit radiation though they are accelerating. The electron does not appear to do work in this orbit.(Note: This is just a statement...so don't qn this...meant only to aid easier understanding). The electron is stable. Hence they do not emit radiation. It is kind of a confinement to a particular region where the external forces do not seem to influence the electrons in any way...


    Got it???

    Sridhar
     
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